Black's Fourth Move Tutorial



1.
[{F:B}{B:rn1qkbnr/ppp2ppp/3p4/4p3/2B1P1b1/2N2N2/PPPP1PPP/R1BQK2R}
{QB:201. After 1. e4 e5  2. Nf3 d6  3. Bc4 Bg4  4. Nc3, which is the better defensive move?{W:201}{A:Bh7h6}{H1:h6}{W:201a}
{A:Bf8e7}{H1:e7}{W:201b};4... h6;{F:B}{B:rn1qkbnr/ppp2ppp/3p4/4p3/2B1P1b1/2N2N2/PPPP1PPP/R1BQK2R}{S:h7h6}{W:201I}Incorrect. This namby-pamby push (4... h7-h6) is a loser. It drops at least a pawn to an unpinning combination, {S:f3e5}{W:201Ia}5. Nf3xe5!. Black has essentially two choices, he can take White's queen{A:Bg4d1}{N1:d1}{W:201Ib}, or he can take White's knight{R}{A:Bd6e5}{N1:e5}{W:201Ic}. Obviously he should start by analyzing what happens upon taking the queen, {R}{C}{S:g4d1}{W:201Id}5... Bg4xd1, because the queen is the greater prize. Taking the queen leads to the c4-bishop's capture on f7 with check {S:c4f7}{W:201Ie}(6. Bc4xf7+). To this intrusion Black has but one response, moving the king to king-two {S:e8e7}{W:201If}(6... Ke8-e7). White then terminates his opponent by {S:c3d5}{W:201Ig}7. Nc3-d5#, a pattern commonly referred to as Legal's Mate. Legal's mate typically occurs by an unpinning combination {F:B}{B:rn1qkbnr/ppp2pp1/3p3p/4p3/2B1P1b1/2N2N2/PPPP1PPP/R1BQK2R}{S:f3e5}{W:201Ih}(5. Nf3xe5), where the winner lets his queen be captured {S:g4d1}{W:201Ii}(5... Bg4xd1) in order to deliver checkmate with the aid of several minor pieces. In our given example, White mates by the teamwork of three minor pieces, both knights and the light-square bishop. If Black sees that taking the queen fails, he could ignore the enemy queen in favor of taking White's venturesome e5-knight {S:d1g4}{P:WQd1}{S:d6e5}{W:201Ij}(5... d6xe5). But then White's queen captures the g4-bishop {S:d1g4}{W:201Ik}(6. Qd1xg4), resulting in White regaining the minor piece and winding up a pawn ahead. Inexperienced players often play moves such as {F:B}{B:rn1qkbnr/ppp2ppp/3p4/4p3/2B1P1b1/2N2N2/PPPP1PPP/R1BQK2R}{S:h7h6}{W:201Il}4... h7-h6, hoping to stop the invasion of an enemy knight. Here Black plays the pawn move to prevent White's f3-knight from going to g5{S:f3g5}{W:201Im}, because he's fearful of a double attack being issued to {N1:f7}{W:201In}f7. (The double attack would come from the knight at {A:Wg5f7}{A:Wc4f7}{W:201Io}g5 and the bishop at c4. But in the given situation, White's tactical alertness enables him to find another method for attacking f7, to take on e5, exposing his own knight to capture, since e5 is apparently guarded by Black's d6-pawn. The tactic, a version of Legal's sacrifice, succeeds however because of the counterattack unveiled by White's queen to the g4-bishop.;4... Be7;{F:B}{B:rn1qkbnr/ppp2ppp/3p4/4p3/2B1P1b1/2N2N2/PPPP1PPP/R1BQK2R}{S:f8e7}{W:201C}Correct. The careful move is 4... Bf8-e7. It stops the Legal trick by clearing the square f8 for Black's king. Now {S:f3e5}{W:201Ca}5. Nf3xe5?? falters because after the queen is seized {S:g4d1}{W:201Cb}(5... Bg4xd1) and the pawn is taken with check {S:c4f7}{W:201Cc}(6. Bc4xf7+), Black's king has an extra escape square at f8 {S:e8f8}{W:201Cd}(6... Ke8-f8). White doesn't have a mate, nor does he have anything to show for his sacrificed queen. Of course White doesn't have to throw away his queen. Instead he can castle {F:B}{B:rn1qk1nr/ppp1bppp/3p4/4p3/2B1P1b1/2N2N2/PPPP1PPP/R1BQK2R}{S:e1g1}{S:h1f1}{W:201Ce}(5. 0-0). He could also move his {N1:d2}{W:201Cf}queen-pawn either one or two squares up. Any of these offer White a fine position with excellent prospects. Yet Black is doing okay, too. He's a little cramped, but his position is solid, and nothing drastic is going to happen to him in the foreseeable future.}]

2.
[{F:B}{B:rnbqkbnr/1ppp1ppp/p1B5/4p3/4P3/5N2/PPPP1PPP/RNBQK2R}
{QB:202. After 1. e4 e5  2. Nf3 Nc6  3. Bb5 a6  4. Bxc6, how should Black take White's bishop?{W:202}{A:Bd7c6}{H1:c6}{W:202a}{A:Bb8c6}{W:202b};4... dxc6;{F:B}{B:rnbqkbnr/1ppp1ppp/p1B5/4p3/4P3/5N2/PPPP1PPP/RNBQK2R}{S:d7c6}{W:202C}Correct. The better capture is with the queen-pawn (4... d7xc6). This violates the principle that encourages taking toward the center when there are two different pawns that can capture on the same square. In capturing this way (4... d7xc6), Black's d-pawn actually moves toward the edge of the board. In the beginning of the game, while you shouldn't ignore pawn placement, you shouldn't invest all your effort and energy worrying about it either. Other factors, such as open lines, development, and king safety, can also be important. Placing too much emphasis on one aspect of play may cause you to minimize another, equally relevant one. By taking away from the center here, Black decides place greater import on activity and development. He specifically opens avenues for two pieces. He unblocks the {N1:c8d7e6f5g4h3}{W:202Ca}c8-h3 diagonal for his queen-bishop, and he clears the {N1:d8d7d6d5d4d3d2d1}{W:202Cb}d-file for his queen. Depending how the game goes, these attacking possibilities could outweigh the liability incurred by accepting doubled pawns. It's the latter clearance, taking away from the center with  4... d7xc6, that enables Black to regain the material most efficiently, after White's f3-knight tries to purloin the e5-pawn {C}{S:f3e5}{W:202Cc}(5. Nf3xe5). With the d-file now unobstructed, Black simply moves his queen up to d4 {S:d8d4}{W:202Cd}(5... Qd8-d4), simultaneously attacking White's knight and pawn. After White salvages the knight, which is the more valuable of the two {S:e5f3}{W:202Ce}(6. Ne5-f3), Black recaptures the king-pawn {S:d4e4}{W:202Cf}(6... Qd4xe4+). This practically forces a trade of queens {S:d1e2}{W:202Cg}(7. Qd1-e2 {S:e4e2}{W:202Ch}Qe4xe2+  {S:e1e2}{W:202Ci}8. Ke1xe2), for the alternative {P:WQd1}{P:BQe4}{S:e2f1}{W:202Cj}(7. Ke1-f1) is far more precarious for White's king. It's hard to recommend forfeiting the right to castle just to keep the queens on the board, especially when doing so gives the opponent the better chances. So White should submit to the queen trade, after which Black's position is truly satisfactory.;4... bxc6;{F:B}{B:rnbqkbnr/1ppp1ppp/p1B5/4p3/4P3/5N2/PPPP1PPP/RNBQK2R}{S:b7c6}{W:202I}Incorrect. Capturing with the b-pawn (4... b7xc6) brings a pawn closer to the center, but it doesn't promote rapid development of the pieces. This is mainly why it's not seen too often in serious competition. Nevertheless it's playable, and it does allow Black to get his pawn back after {S:f3e5}{W:202Ia}5. Nf3xe5. He simply delivers a queen fork, {S:d8g5}{W:202Ib}5... Qd8-g5, synchronously attacking the {A:Bg5e5}{N1:e5}{W:202Ic}e5-knight and the {A:Bg5g2}{N1:g2}{W:202Id}g2-pawn, neither of which are protected. Naturally White will save his knight and cede the g2-pawn. After {R}{C}{S:e5f3}{W:202Ie}6. Ne5-f3 {S:g5g2}{W:202If}Qg5xg2 {S:h1g1}{W:202Ig}7. Rh1-g1 {S:g2h3}{W:202Ih}Qg2-h3, it's a complicated game with chances for both sides.}]

3.
[{F:B}{B:r1bqkb1r/pppp1ppp/2n2n2/4p1N1/2B1P3/8/PPPP1PPP/RNBQK2R}
{QB:203. After 1. e4 e5  2. Nf3 Nc6  3. Bc4 Nf6  4. Ng5, which is the better defense?{W:203}{A:Bd8e7}{H1:e7}{W:203a}{A:Bd7d5}{H1:d5}{W:203b};4... Qe7;{F:B}{B:r1bqkb1r/pppp1ppp/2n2n2/4p1N1/2B1P3/8/PPPP1PPP/RNBQK2R}{S:d8e7}{W:203I}Incorrect. The move 4... Qd8-e7 is the inferior of the two choices, but it does set a slimy trap. If White continues {S:g5f7}{W:203Ia}5. Ng5xf7, Black can counter with the block, {S:d7d5}{W:203Ib}5... d7-d5!, gaining time by attacking the bishop that protects the knight. White can take the d-pawn {S:e4d5}{W:203Ic}(6. e4xd5), but Black's queen steals the knight {S:e7f7}{W:203Id}(6... Qe7xf7) while pinning the d-pawn to the bishop. If White then takes the knight {S:d5c6}{W:203Ie}(7. d5xc6), the queen takes the bishop {S:f7c4}{W:203If}(7... Qf7xc4), leaving Black ahead by a minor piece. White, however, doesn't have to play 6. e4xd5. Instead the invasionary knight can take the rook {F:B}{B:r1b1kb1r/ppp1qNpp/2n2n2/3pp3/2B1P3/8/PPPP1PPP/RNBQK2R}{S:f7h8}{W:203Ig}(6. Nf7xh8), whereupon Black captures the bishop {S:d5c4}{W:203Ih}(6... d5xc4). At this point White is up the exchange. (You are up the exchange if you have a rook and your opponent has a minor piece.) But there's a good chance that Black will also acquire the knight at {N1:h8}{W:203Ii}h8, for it's cornered and has no apparent escape. Afterward Black will have two minor pieces against a rook, which constitutes a clear material advantage. But White could sidestep all this. After {F:B}{B:r1bqkb1r/pppp1ppp/2n2n2/4p1N1/2B1P3/8/PPPP1PPP/RNBQK2R}{S:d8e7}{W:203Ij}4... Qd8-e7, instead of taking on f7 with his knight{A:Wg5f7}{N1:f7}{W:203Ik}, he could invade with his bishop {R}{C}{S:c4f7}{W:203Il}(5. Bc4xf7+). This gives check and freezes the action. Black's king is driven to d8 {S:e8d8}{W:203Im}(5... Ke8-d8), and White has the time to tidy up house by retreating the bishop {S:f7b3}{W:203In}to b3, where it's safer than it was at c4. By moving the bishop to safety, White also insures the bishop's survival in case the {N1:g5}{W:203Io}g5-knight is chased away by a subsequent {S:h7h6}{W:203Ip}h7-h6. Many players mechanically make this mistake. That is, when they have the choice of invading with the knight (for instance, Ng5-f7), attacking the rook in the corner, or taking with the bishop (Bc4xf7+), giving check and making the enemy king move, they perfunctorily barge in with the knight. Blinded by the chance to win the rook, they often undervalue the benefit of forcing the opponent's king to move. Sometimes it's better to take with the knight, sometimes with the bishop, and only move-by-move analysis, not generalized assumptions, can help you decide wisely. Here {F:B}{B:r1bqkb1r/pppp1ppp/2n2n2/4p1N1/2B1P3/8/PPPP1PPP/RNBQK2R}{S:d8e7}{W:203Iq}4... Qd8-e7 is refuted by {S:c4f7}{W:203Ir}5. Bc4xf7+. White winds up winning a pawn. He also forces Black's king to move{S:e8d8}{W:203Is}, which deprives it of the castling privilege. Finally White's produced a more serious invasionary menace, the threat to invade on f7 with the knight, when it really means something, forking the king and rook with check {S:g5f7}{W:203It}(7. Ng5-f7+). These are good enough reasons to avoid playing 4... Qd8-e7.;4... d5;{F:B}{B:r1bqkb1r/pppp1ppp/2n2n2/4p1N1/2B1P3/8/PPPP1PPP/RNBQK2R}{S:d7d5}{W:203C}Correct. The superior defense is offered by 4... d7-d5, which blocks out the {N1:c4}c4-bishop (so that it's no longer attacking f7). Moreover, the c4-bishop is actually threatened by this advance, so that White is constrained to make decisions. After 4... d7-d5, two lines can be dismissed as being good for Black. The first entails the bishop's retreat {S:c4b3}{W:203Ca}(5. Bc4-b3?). This loses a pawn to the capture {S:f6e4}{W:203Cb}(5... Nf6xe4). Another move that can be discharged is taking the pawn with the bishop {F:B}{B:r1bqkb1r/ppp2ppp/2n2n2/3pp1N1/2B1P3/8/PPPP1PPP/RNBQK2R}{S:c4d5}{W:203Cc}(5. Bc4xd5). Black is riding high after {S:f6d5}{W:203Cd}5... Nf6xd5 {S:e4d5}{W:203Ce}6. e4xd5 {S:d8d5}{W:203Cf}Qd8xd5, for the material is even and the threats have been answered. White's best continuation is to capture on d5 with the pawn {F:B}{B:r1bqkb1r/ppp2ppp/2n2n2/3pp1N1/2B1P3/8/PPPP1PPP/RNBQK2R}{S:e4d5}{W:203Cg}(5. e4xd5). At this point Black's replies can get quite tricky, and the analysis is best left for another occasion. For now all you need to know is that by playing 
4... d7-d5 Black is very much in the game.}]

4.
[{F:B}{B:r1bqkbnr/pppp1ppp/2n5/8/3NP3/8/PPPP1PPP/RNBQKB1R}
{QB:204. After 1. e4 e5  2. Nf3 Nc6  3. d4 exd4  4. Nxd4, which is the better way to fight for the center?{W:204}{A:Bf8c5}{H1:c5}{W:204a}{A:Bd7d6}{H1:d6}{W:204b};4... Bc5;{F:B}{B:r1bqkbnr/pppp1ppp/2n5/8/3NP3/8/PPPP1PPP/RNBQKB1R}{S:f8c5}{W:204C}Correct. Exert pressure against {N1:d4}{W:204Ca}d4 by developing the king-bishop (4... Bf8-c5). (Another good developing move with the king-bishop is {C}{A:Bf8b4}{W:204Cb}4... Bf8-b4, pinning the {S:b1c3}{W:204Cc}c3-knight.) In posting the king-bishop on c5, Black activates a new piece with a gain of time by threatening to win the {R}{S:c3b1}{N1:d4}{W:204Cd}d4-knight. White may respond to the threat by exchanging knights on {A:Wd4c6}{N1:c6}{W:204Ce}c6, retreating to {R}{A:Wd4b3}{N1:b3}{W:204Cf}b3, or defending the {R}{N1:d4}{W:204Cg}d4-knight. No matter, Black has respectable resources against these contingencies, thanks to the active stance assumed by 4... Bf8-c5.;4... d6;{F:B}{B:r1bqkbnr/pppp1ppp/2n5/8/3NP3/8/PPPP1PPP/RNBQKB1R}{S:d7d6}{W:204I}Incorrect. The move of the queen-pawn (4... d7-d6) is terribly conservative, for it needlessly hems in the {N1:f8}{W:204Ia}f8-bishop. Before moving the queen-pawn one-square, it's first desirable to mobilize the king-bishop to {A:Bf8c5}{A:Bf8b4}{W:204Ib}c5 or b4. With 4... d7-d6, Black envisions a follow-up plan of actuating the kingside knight {R}{C}{S:g8f6}{W:204Ic}(5... Ng8-f6) and bishop {S:f8e7}{W:204Id}(6... Bf8-e7). Then Black will castle {S:e8g8}{S:h8f8}{W:204Ie}(7... 0-0). This establishes a solid defensive formation that's hard to crack. The downside is that Black fashions a game with no activity whatsoever. His pieces are placed passively, while White obtains an easy time developing, with greater operating space in the center. Add to this mix the growing initiative White augments because of Black's milquetoast approach, and White's overall advantage is 
assured.}]

5.
[{F:B}{B:rnbqkbnr/ppp2ppp/8/3P4/5p2/5N2/PPPP2PP/RNBQKB1R}
{QB:205. After 1. e4 e5  2. f4 d5  3. exd5 exf4  4. Nf3, should Black take or develop?{W:205}{A:Bd8d5}{H1:d5}{W:205a}{A:Bg8f6}{H1:f6}{W:205b};4... Qxd5;{F:B}{B:rnbqkbnr/ppp2ppp/8/3P4/5p2/5N2/PPPP2PP/RNBQKB1R}{S:d8d5}{W:205I}Incorrect. Don't go pawn-grabbing with 4... Qd8xd5. Black ends up losing too much time with his queen and White's initiative goes unchecked. In some instances White's pieces come pouring out of the box faster than Black can deal with them. Let's say that White starts the assault by developing the queen-knight {S:b1c3}{W:205Ia}(5. Nb1-c3), which attacks the queen and forces it to flee to safety. If Black tries to pursue this ersatz line of attack with {S:d5e6}{W:205Ib}5... Qd5-e6+, White doesn't bother to block the check at all. Rather he manufactures a further possibility of aggression by moving the king out of the way {S:e1f2}{W:205Ic}(6. Ke1-f2!). (In chess it's often possible to turn adversity into advantage.) Moving the king to f2 clears {N1:e1}{W:205Id}e1 for use by the king-rook, and if Black is not careful, he can get his queen pinned or worse. An illustration is the continuation {C}{S:f8c5}{W:205Ie}6... Bf8-c5+. This too is a pointless check, for it compels White to improve his game by blocking the check {S:d2d4}{W:205If}(7. d2-d4). (Try not to make moves that force your opponent to better his position.) After the necessary retreat, {S:c5b6}{W:205Ig}7... Bc5-b6, White answers with his own check, {S:f1b5}{W:205Ih}8. Bf1-b5+. This check is reasonable, however, for it clears the home rank with a gain of time. Black is coerced into moving his king off the e-file {S:e8d8}{W:205Ii}(8... Ke8-d8), to avoid the looming pin of White's king-rook. But White plays {S:h1e1}{W:205Ij}9. Rh1-e1 anyway, and if Black saves his queen by {S:e6f6}{W:205Ik}9... Qe6-f6, it's mate {S:e1e8}{W:205Il}(10. Re1-e8#). True, this example is exaggerated, but it clearly shows the dangers in the position for the unwary defender. Don't bring out the queen so early unless you know or sense it's the right thing to do. Otherwise, you're probably asking for it.;4... Nf6;{F:B}{B:rnbqkbnr/ppp2ppp/8/3P4/5p2/5N2/PPPP2PP/RNBQKB1R}{S:g8f6}{W:205C}Correct. The development of the king-knight (4... Ng8-f6) is in order. In doing this, Black announces that his top priority is to castle, getting his king out of the exposed center. The open e-file is the tip-off. At any moment White might place a major piece (queen or rook) on the e-file to check the enemy king, pin an enemy unit to the king, or simply tie down Black's forces to passivity. As a rule, you can't really begin operations until your king is safely ensconced, where it can't easily be harassed. As far as taking White's {N1:d5}{W:205Ca}d-pawn, this now becomes mainly the province of Black's {A:Bf6d5}{W:205Cb}f6-knight (and not so much Black's queen), if in the future capturing with the knight (Nf6xd5) is feasible.}]

6.
[{F:B}{B:rnbqkbnr/pp2pppp/3p4/8/3NP3/8/PPP2PPP/RNBQKB1R}
{QB:206. After 1. e4 c5  2. Nf3 d6  3. d4 cxd4  4. Nxd4, should Black develop a knight or attack one?{W:206}{A:Bg8f6}{H1:f6}{W:206a}{A:Be7e5}{H1:e5}{W:206b};4... Nf6;
{B:rnbqkbnr/pp2pppp/3p4/8/3NP3/8/PPP2PPP/RNBQKB1R}{S:g8f6}{W:206C}Correct. The most purposeful move here is 4... Ng8-f6. Black thereby begins the counterplay against White's e-pawn, the only pawn actually on a center square. This plan also explains Black's second move {N1:d6}{W:206Ca}(2... d7-d6). Not only did it release the {R}{N1:c8}{W:206Cb}queen-bishop, it also fixed White's {N1:e4}{W:206Cc}king-pawn in place by guarding the square in front of it. With {N1:e5}{W:206Cd}e5 controlled by Black, White will find it harder to advance the king-pawn once Black starts to zero in on it. After Black develops the king-knight (4... Ng8-f6), then he can decide what he wants to do with his own {N1:e7}{W:206Ce}e-pawn. There are three options. He can leave the king-pawn on e7, choosing to develop the king-bishop on the flank (at g7). He can advance it one square ahead, to {A:Be7e6}{W:206Cf}e6, to maintain influence over the {N1:d5}{W:206Cg}d5-square. Or he can move it up two squares{R}{C}{A:Be7e5}{W:206Ch}, to contest the critical point {N1:d5}{W:206Ci}d4. Since all three formations require a Black knight at {R}{N1:f6}{W:206Cj}f6, it's logically consistent to develop it to f6 at once, on move four.;4... e5;{F:B}{B:rnbqkbnr/pp2pppp/3p4/8/3NP3/8/PPP2PPP/RNBQKB1R}{S:e7e5}{W:206I}Incorrect. It's not yet a good idea to play the pawn up to king-four (4... e7-e5). Played too early, it leaves a trail of weakened light squares at {N1:d5f5}{W:206Ia}d5 and f5 (squares that can no longer be guarded by Black's e-pawn). To capitalize on Black's mistake, White must first nullify the {N1:c8}{W:206Ib}c8-bishop by giving check {C}{S:f1b5}{W:206Ic}(5. Bf1-b5+). If Black blocks the check with the queen-knight {S:b8d7}{W:206Id}(5... Nb8-d7), then White's knight immediately invades {S:d4f5}{W:206Ie}(6. Nd4-f5). Since the {N1:c8}{W:206If}c8-bishop has lost control of {N1:f5}{W:206Ig}f5, because the {N1:d7}{W:206Ih}d7-knight obstructs the diagonal, White's knight is safe from capture. Nor does it help to block the check {F:B}{B:rnbqkbnr/pp3ppp/3p4/4p3/3NP3/8/PPP2PPP/RNBQKB1R}{S:f1b5}{W:206Ii}(5. Bf1-b5+) with the queen-bishop {S:c8d7}{W:206Ij}(5... Bc8-d7), for White trades bishops {S:b5d7}{W:206Ik}(6. Bb5xd7+ {A:Bb8d7}{N1:d7}{W:206Il}Nb8xd7, or {A:Bd8d7}{W:206Im}6... Qd8xd7), {R}{C}{S:d8d7}{W:206In}and White's knight comes in {S:d4f5}{W:206Io}(7. Nd4-f5) anyway. In both cases, whether Black blocks at d7 with the knight or the bishop, White keeps a grip on d5 and establishes his knight on f5. Meanwhile, Black's only way to get rid of the f5-knight is by the weakening prod {S:g7g6}{W:206Ip}g7-g6. Clearly, advancing the king-pawn two squares ahead (4... e7-e5) on move four is somewhat premature. It allows White to improve his chances without  counterbalancing gain.}]

7.
[{F:B}{B:rnbqkbnr/pp3ppp/4p3/2ppP3/3P4/2P5/PP3PPP/RNBQKBNR}
{QB:207. After 1. e4 e6  2. d4 d5  3. e5 c5  4. c3, should Black end the central tension or maintain it?{W:207}{A:Bc5d4}{H1:d4}{W:207a}{A:Bb8c6}{H1:c6}{W:207b};4... cxd4;{F:B}{B:rnbqkbnr/pp3ppp/4p3/2ppP3/3P4/2P5/PP3PPP/RNBQKBNR}{S:c5d4}{W:207I}Incorrect. It's wiser to hold up the exchange and not play 4... c5xd4. After White takes back {S:c3d4}{W:207Ia}(5. c3xd4), Black has nothing better than developing the queen-knight {S:b8c6}{W:207Ib}(5... Nb8-c6), which could be done a move earlier without releasing the tension. (You release tension by ending the possibility of future pawn exchanges, either by trading pawns or pushing the capturable pawn past the point of exchange.) White is the one who benefits from this unnecessary pawn exchange, because it clears the square c3 for the queen-knight. Before the exchange, c3 is blocked by the c-pawn, making it impossible for White to place the b1-knight on this optimal square. So by taking (4... c5xd4) Black actually increases White's options.;4... Nc6;{F:B}{B:rnbqkbnr/pp3ppp/4p3/2ppP3/3P4/2P5/PP3PPP/RNBQKBNR}{S:b8c6}{W:207C}Correct. It's better for Black to retain the tension by developing the queen-knight (4... Nb8-c6). Furthermore, Black needn't worry about the possibility of White's queen-pawn taking on c5 {S:d4c5}{W:207Ca}(5. d4xc5), for this would undermine the support for the {N1:e5}{W:207Cb}e5-pawn. It's this e5-pawn that keeps Black constricted, in that it impedes the movement of Black's own king-pawn, which in turn obstructs the movement of Black's c8-bishop (the so-called problem bishop). What this means is that Black controls the tension at the key exchange points, {N1:c5d4}{W:207Cc}c5 and d4. It's Black who has the option of taking on d4. It's Black who can decide when and if to push past (c5-c4). And it's Black who can mount the pressure against {N1:d4}{W:207Cd}d4 by positioning his queen at b6. This deployment {S:d8b6}{W:207Ce}(5... Qd8-b6) also restricts the development of White's queen-bishop, for it places {N1:b2}{W:207Cf}b2 under surveillance. If the c1-bishop moves, Black's queen may be able to take on b2 for free. All in all, the balance sheet after 4... Nb8-c6 reads that White has more space (because of his advanced e5-pawn), but Black has control of the tension (because White can't yet afford to take on c5). The chances are about equal.}]

8.
[{F:B}{B:rnbqkbnr/pp2pppp/2p5/8/3PN3/8/PPP2PPP/R1BQKBNR}
{QB:208. After 1. e4 c6  2. d4 d5  3. Nc3 dxe4  4. Nxe4, should Black move a pawn or a bishop?{W:208}{A:Be7e6}{H1:e6}{W:208a}{A:Bc8f5}{H1:f5}{W:208b};4... e6;{F:B}{B:rnbqkbnr/pp2pppp/2p5/8/3PN3/8/PPP2PPP/R1BQKBNR}{S:e7e6}{W:208I}Incorrect. If Black plays the passive 4... e7-e6, he's made one too many pawn moves to start the game. It was time to get some pieces out, and three moves come to mind. He could develop his queen-bishop {A:Bc8f5}{W:208Ia}(4... Bc8-f5), his king-knight {R}{A:Bg8f6}{W:208Ib}(4... Ng8-f6), or his queen-knight {R}{A:Bb8d7}{W:208Ic}(4... Nb8-d7). The latter development is part of a two-move idea, where Black follows up with the king-knight {A:Bg8f6}{W:208Id}(5... Ng8-f6), so that the queen-knight protects it. This avoids doubled pawns in the event of an exchange on f6. As far as the e-pawn goes, it can be advanced later, preferably after the queen-bishop has been activated to {R}{A:Bc8f5}{W:208Ie}f5 (or possibly g4). In this manner Black avoids locking the light-square bishop inside the pawn chain, averting the creation of a "problem bishop.";4... Bf5;{F:B}{B:rnbqkbnr/pp2pppp/2p5/8/3PN3/8/PPP2PPP/R1BQKBNR}{S:c8f5}{W:208C}Correct. The better move is 4... Bc8-f5, which begins to challenge White's central dominance. White has the temporary edge in the middle because of the placement of a pawn on d4 and a knight on e4. Black can't afford to let White have a free hand in the center, and developing the bishop to f5 essentially compels the e4-knight's removal from the region. The best repositioning is to retreat the knight {S:e4g3}{W:208Ca}(5... Ne4-g3), because this replacement enables White to gain back a tempo. The attacked e4-knight has metamorphosed into the attacking g3-knight, and Black must expend a move extricating the f5-bishop from danger {S:f5g6}{W:208Cb}(5... Bf5-g6). But Black has accomplished his mission. He's coerced White into withdrawing the e4-knight from the center. Now Black can focus on the d4-pawn, which he will start operations against by virtue of the subsequent pawn pushes {A:Be7e5}{A:Bc6c5}{W:208Cc}e7-e5 and c6-c5. These advances should keep the game honest.}]

9.
[{F:B}{B:rnbqkb1r/pppppppp/1n6/4P3/2PP4/8/PP3PPP/RNBQKBNR}
{QB:209. After 1. e4 Nf6  2. e5 Nd5  3. c4 Nb6  4. d4, how should Black begin the assault against White's mighty pawn center?{W:209}{A:Bb8c6}{H1:c6}{W:209a}{A:Bd7d6}{H1:d6}{W:209b};4... Nc6;{F:B}{B:rnbqkb1r/pppppppp/1n6/4P3/2PP4/8/PP3PPP/RNBQKBNR}{S:b8c6}{W:209I}Incorrect. Not 4... Nb8-c6, because then matters really get out of hand. White responds with {S:f2f4}{W:209Ia}5. f2-f4, supporting the king-pawn. Now when Black tries to undermine e5 with {S:d7d6}{W:209Ib}5... d7-d6, it comes too late. White advances {S:d4d5}{W:209Ic}6. d4-d5, driving the {N1:c6}{W:209Id}c6-knight from the central zone, without repercussions to {N1:e5}{W:209Ie}e5 because it's protected by the {N1:f4}{W:209If}f4-pawn. Timing is crucial. The way to shake up the White center is by launching the softening d7-d6 on move four, not move five. Developing the queen-knight to c6 simply doesn't work without the preparatory 4... d7-d6. Do it when you need to, or you won't need to do it at all.;4... d6;{F:B}{B:rnbqkb1r/pppppppp/1n6/4P3/2PP4/8/PP3PPP/RNBQKBNR}{S:d7d6}{W:209C}Correct. The right continuation is 4... d7-d6, challenging White's e5-pawn at once. If White tries to provide support at this point {S:f2f4}{W:209Ca}(5. f2-f4), he runs into {S:d6e5}{W:209Cb}5... d6xe5  {S:f4e5}{W:209Cc}6. f4xe5 {S:b8c6}{W:209Cd}Nb8-c6, hitting e5 again. Now the advance {S:d5d6}{W:209Ce}7. d5-d6 is ruled out because it hangs the White king-pawn {S:c6e5}{W:209Cf}(7... Nc6xe5). So White must spend a tempo to defend the menaced d4-pawn. If he does so by {S:g1f3}{W:209Cg}8. Ng1-f3, Black can activate the queen-bishop, pinning the f3-knight {S:c8g4}{W:209Ch}(8... Bc8-g4). This renews the threat to d4 and White must secure this square once more. It's also clear that Black has generated the kind of pressure he needs to get a proper share of the play. Note that Black must play 5... d6xe5 before developing the queen-knight. If on move five he delays this exchange and instead brings out the queen-knight immediately{F:B}{B:rnbqkb1r/ppp1pppp/1n1p4/4P3/2PP1P2/8/PP4PP/RNBQKBNR}{S:b8c6}{W:209Ci} (5... Nb8-c6), he transposes into the line where White gets to drive the knight away by {S:d4d5}{W:209Cj}6. d4-d5. And, as before, the knight can't take the e5-pawn, in that it's defended by the pawn on f4.}]

10.
[{F:B}{B:rnb1kbnr/ppp1pppp/8/q7/3P4/2N5/PPP2PPP/R1BQKBNR}
{QB:210. After 1. e4 d5  2. exd5 Qxd5  3. Nc3 Qa5  4. d4, which is the better pawn move?{W:210}{A:Bc7c6}{H1:c6}{W:210a}{A:Be7e6}{H1:e6}{W:210b};4... c6;{F:B}{B:rnb1kbnr/ppp1pppp/8/q7/3P4/2N5/PPP2PPP/R1BQKBNR}{S:c7c6}{W:210C}Correct. The semi-waiting move, 4... c7-c6, is best. The situation of the Black queen on {N1:a5}{W:210Ca}a5 could soon become uncomfortable. By moving the c-pawn, Black provides a convenient retreat for the queen once things get too hot. Her majesty could thereafter transfer to {N1:c7d8}{W:210Cb}c7 or d8 whenever necessary or pragmatic. The other point about c7-c6 is that it doesn't close off the diagonal of the {N1:c8}{W:210Cc}c8-bishop, as does the move {A:Be7e6}{W:210Cd}4... e7-e6. By not yet moving the e-pawn, Black is still able to position the queen-bishop usefully, either to {R}{A:Bc8f5}{W:210Ce}f5, to influence the {N1:b1c2d3e4f5g6h7}{W:210Cf}b1-h7 diagonal, or to {R}{C}{A:Bc8g4}{W:210Cg}g4, to pin the king-knight once it's stationed at {N1:f3}{W:210Ch}f3.;4... e6;{F:B}{B:rnb1kbnr/ppp1pppp/8/q7/3P4/2N5/PPP2PPP/R1BQKBNR}{S:e7e6}{W:210I}Incorrect. Playing 4... e7-e6 is an unfortunate piece of chess timing. It instantly seals the {N1:c8}{W:210Ia}c8-bishop inside the pawn chain, reducing Black's queen-bishop to the status of an imprisoned piece. What this means is that Black will play most of the opening behind by a piece, since the queen-bishop won't be able to contribute very much. This also suggests that Black's overall attacking capabilities will be greatly diminished. The move 4... e7-e6 might also wind up losing a tempo, because in many situations Black will want to advance the king-pawn to e5 to attack d4. Since this could be done in one move if Black's king-pawn were back on e7, playing the king-pawn to e6 wastes a move that might otherwise be used productively. So, on move four, instead of moving the king-pawn to {N1:e6}{W:210Ib}e6, hold it back in favor of advancing the queen-bishop pawn to {S:e6e7}{S:c7c6}{W:210Ic}c6. As a chessplayer, you'll likely to live a lot longer this way.}]

11.
[{F:B}{B:rnbqkb1r/ppp1pppp/5n2/8/2pP4/4PN2/PP3PPP/RNBQKB1R}
{QB:211. After 1. d4 d5  2. c4 dxc4  3. Nf3 Nf6  4. e3, should Black block his c-pawn or his c8-bishop?{W:211}{A:Bb8c6}{H1:c6}{W:211a}{A:Be7e6}{H1:e6}{W:211b};4... Nc6;{F:B}{B:rnbqkb1r/ppp1pppp/5n2/8/2pP4/4PN2/PP3PPP/RNBQKB1R}{S:b8c6}{W:211I}Incorrect. The move with the queen-knight (4... Nb8-c6) is all wrong. The only way that Black can put pressure on White's center now is by advancing the king-pawn two squares {A:Be7e5}{W:211Ia}(e7-e5). But Black will never be able to implement this move. White already has a two-to-one edge on e5 (the {R}{N1:d4f3}{W:211Ib}d4-pawn and the f3-knight vs. the {N1:c6}{W:211Ic}c6-knight), and there aren't many ways that Black can add to his e5-arsenal. Nor is it going to be easy for Black to deploy his queen-bishop. For example, after 4... Nb8-c6 {C}{S:f1c4}{W:211Id}5. Bf1xc4 {S:c8g4}{W:211Ie}Bc8-g4?, White wins a pawn by the double attack, {S:d1b3}{W:211If}6. Qd1-b3, hitting both {A:Bb3b7}{A:Bc4f7}{N1:f7b7}{W:211Ig}b7 and f7. Generally, whenever the queen-bishop is developed early, it leaves the queen-knight-two square {R}{N1:b7b2}{W:211Ih}(b7 for Black, b2 for White) vulnerable to tactics, such as the above double attack. Perhaps the biggest problem with 4... Nb8-c6 is that it blocks the c-pawn. This means that, to get central play, Black is going to have to rely on moving his king-pawn. But the prospects of this advance materializing in the near future are very slim.;4... e6;{F:B}{B:rnbqkb1r/ppp1pppp/5n2/8/2pP4/4PN2/PP3PPP/RNBQKB1R}{S:e7e6}{W:211C}Correct. The right move is 4... e7-e6. It's relevant to Black's first order of business, which is to get pressure against White's center. This Black will soon do by advancing the c-pawn to {S:c7c5}{W:211Ca}c5, assailing White's d-pawn and making it possible to open the c-file by exchanging pawns {S:c5d4}{W:211Cb}(c5xd4). The closing of the c8-h3 diagonal resulting from moving the king-pawn to {N1:e6}{W:211Cc}e6 is not critical in this situation, for Black has another way to activate his queen-bishop. He can flank it at {C}{A:Bc8b7}{N1:b7}{W:211Cd}b7 after first playing the a-pawn to {S:a7a6}{W:211Ce}a6 and then moving the b-pawn to {S:b7b5}{W:211Cf}b5. Of course, Black is yet to achieve all this, but he has good chances of doing so, which renders his game quite playable.}]

12.
[{F:B}{B:rnbqkb1r/ppp2ppp/4pn2/3p2B1/2PP4/2N5/PP2PPPP/R2QKBNR}
{QB:212. After 1. d4 d5  2. c4 e6  3. Nc3 Nf6  4. Bg5, how should Black deal with the pin on his knight?{W:212}{A:Bf8e7}{H1:e7}{W:212a}{A:Bh7h6}{H1:h6}{W:212b};4... Be7;{F:B}{B:rnbqkb1r/ppp2ppp/4pn2/3p2B1/2PP4/2N5/PP2PPPP/R2QKBNR}{S:f8e7}{W:212C}Correct. Breaking the pin by developing the dark-square bishop (4... Bf8-e7) is the preferred reply. This frees the king-knight so that it can once again take part in the central festivities, overlooking the middle squares {N1:e4d5}{W:212Ca}e4 and d5. Meanwhile, the space between Black's king and king-rook has cleared, so that castling kingside can now be effectuated at any moment. Finally the move 4... Bf8-e7 is weakness-free. No new soft spots have been engendered in the Black camp because of it.;4... h6;{F:B}{B:rnbqkb1r/ppp2ppp/4pn2/3p2B1/2PP4/2N5/PP2PPPP/R2QKBNR}{S:h7h6}{W:212I}Incorrect. Attacking the g5-bishop by 4... h7-h6 is a positional mistake. White's bishop will simply capture on f6 {S:g5f6}{W:212Ia}(5. Bg5xf6), when Black's queen is unable to take back because of its ties to the d-pawn. If {S:d8f6}{W:212Ib}5... Qd8xf6, then {S:c4d5}{W:212Ic}6. c4xd5 {S:e6d5}{W:212Id}e6xd5 {S:c3d5}{W:212Ie}7. Nc3xd5 simply gains a pawn. So, to avoid this material loss, Black is compelled to recapture on f6 with the g-pawn {F:B}{B:rnbqkb1r/ppp2pp1/4pB1p/3p4/2PP4/2N5/PP2PPPP/R2QKBNR}{S:g7f6}{W:212If}(5... g7xf6). Thereafter White can shatter Black's kingside pawn structure completely by exchanging pawns on d5 {S:c4d5}{W:212Ig}(6. c4xd5 {S:e6d5}{W:212Ih}e6xd5). The resulting Black kingside is punctuated with holes, in that he has doubled isolated pawns on the f-file {N1:f6f7}{W:212Ii}and a single isolated pawn on the {N1:h6}{W:212Ij}h-file. Breaking it down to its rudiments, the square {N1:f5}{W:212Ik}f5 is ripe for invasion by a White knight, for Black doesn't have a pawn on an adjacent file that can guard f5. So Black doesn't have a satisfactory way to keep the knight out. Moreover, pawn protection is not possible for the pawns at {N1:f6h6}{W:212Il}f6 and h6. Thus they will require constant protection by Black pieces to avoid being overtaken by the marauding White forces. And don't ask where Black's king is to find safety, for the {N1:g1g2g3g4g5g6g7g8}{W:212Im}g-file, the very file Black's king winds up on after castling kingside, is devoid of pawn shelter. This means that once castled Black's king would be terribly exposed to the elements. There are just too many problems here, so prudence recommends avoiding them in the first place by not playing 4... h7-h6.}]

13.
[{F:B}{B:rn1qkbnr/pp2pppp/2p5/3p1b2/2PP4/2N2N2/PP2PPPP/R1BQKB1R}
{QB:213. After 1. d4 d5 2. c4 c6  3. Nf3 Bf5  4. Nc3, should Black exercise restraint or can he win a pawn?{W:213}{A:Be7e6}{H1:e6}{W:213a}{A:Bd5c4}{H1:c4}{W:213b};4... e6;{F:B}{B:rn1qkbnr/pp2pppp/2p5/3p1b2/2PP4/2N2N2/PP2PPPP/R1BQKB1R}{S:e7e6}{W:213C}Correct. Since there is no chance to win a pawn, Black should show some reserve and move up the king-pawn, 4... e7-e6. The advance of the king-pawn strengthens {N1:d5}{W:213Ca}d5, while opening a path for {N1:f8}{W:213Cb}the dark-square bishop. For the meantime, with both the {N1:c6e6}{W:213Cc}c- and e-pawns backing up Black's {N1:d5}{W:213Cd}d5-pawn, Black is playing a so-called strongpoint defense, with a securely protected queen-pawn at the head of a central wedge. There's really only one way that White can try to cause trouble after 4... e7-e6, and this is by developing the queen to {C}{S:d1b3}{W:213Ce}b3, menacing the undefended pawn at {A:Wb3b7}{N1:b7}{W:213Cf}b7. The b-pawn typically loses its natural protection when the queen-bishop is developed early (here, 3... Bc8-f5). In the event of 5. Qd1-b3, Black can save the day by activating his own queen, placing it on b6 and offering a queen trade in the process. After {R}{C}{S:d8b6}{W:213Cg}5... Qd8-b6 {S:b3b6}{W:213Ch}6. Qb3xb6 {S:a7b6}{W:213Ci}a7xb6, Black's queenside pawn structure is slightly impaired, but he gets an open {N1:a8a7a6a5a4a3a2a1}{W:213Cj}a-file for his queen-rook, which more than offsets the weakened pawns.;4... dxc4;{F:B}{B:rnbqkbnr/pp2pppp/2p5/3p1b2/2PP4/2N2N2/PP2PPPP/R1BQKB1R}{S:d5c4}{W:213I}Incorrect. Taking the queen-bishop pawn by 4... d5xc4 runs into a buzz saw. By loosening his grip on e4, Black allows an immediate strike with {S:e2e4}{W:213Ia} 5. e2-e4, kicking Black's queen-bishop in the face. Black will have to waste a move saving this bishop, while White's own light-square bishop obtains an open diagonal {N1:f1e2d3c4b5a6}{W:213Ib}(f1-a6) without loss of time. If Black tries to fight for his stolen booty (the c4-pawn), retreating his bishop to e6 to defend it {C}{S:f5e6}{W:213Ic}(5... Bf5-e6), White pushes the queen-pawn to d5 {S:d4d5}{W:213Id}(6. d4-d5) and soon regains the pawn on c4 {S:c6d5}{W:213Ie}(6... c6xd5 {S:e4d5}{W:213If}7. e4xd5 {S:e6g4}{W:213Ig}Be6-g4  {S:f1c4}{W:213Ih}8. Bf1xc4). The end result is that Black has surrendered the center, lost space and time, and has nothing to show for his efforts. Advantage White.}]

14.
[{F:B}{B:rnbqk2r/ppppbppp/4pn2/8/2PP4/5NP1/PP2PP1P/RNBQKB1R}
{QB:214. After 1. d4 Nf6  2 c4 e6  3. Nf3 Be7  4. g3, should Black start a fianchetto or check with his king-bishop?{W:214}{A:Bb7b6}{H1:b6}{W:214a}{A:Be7b4}{H1:b4}{W:214b};4... b6;{F:B}{B:rnbqk2r/ppppbppp/4pn2/8/2PP4/5NP1/PP2PP1P/RNBQKB1R}{S:b7b6}{W:214C}Correct. Work on developing a new piece with 4... b7-b6. It's clear that the c8-bishop can hardly be mobilized along the {N1:c8d7e6f5g4h3}{W:214Ca}c8-h3 diagonal, for both {N1:d7e6}{W:214Cb}d7 and e6 are presently blocked by pawns. The logical thing to do therefore is to find another diagonal for the bishop. With 4... b7-b6 Black prepares to fianchetto the c8-bishop at {C}{S:c8b7}{W:214Cc}b7, when the light-square bishops for both sides will then occupy the same diagonal {N1:a8b7c6d5e4f3g2h1}{W:214Cd}(a8-h1) and can contest the same critical middle squares, {N1:d5e4}{W:214Ce}d5 and e4. The play then moves along the standard lines of the Queen's Indian Defense, in which Black attempts to dominate the middle mainly with piece play, rather than pawn advances.;4... Bb4+;{F:B}{B:rnbqk2r/ppppbppp/4pn2/8/2PP4/5NP1/PP2PP1P/RNBQKB1R}{S:e7b4}{W:214I}Incorrect. Moving the dark-square bishop again, 4... Be7-b4+, for the second turn in a row, is a loss of time. If Black had wanted to develop his bishop to b4, he could have done so on move three, saving a tempo. Now White has essentially the same position, but with the useful move 4. g2-g3 thrown in for free. It generally requires an unusual set of circumstances to justify moving the same piece twice in the opening. A successful example of this violation to principle occurs after {F:B}{B:rnbqk2r/ppppbppp/4pn2/8/2PP4/5NP1/PP2PP1P/RNBQKB1R}{S:b7b6}{W:214Ia}4... b7-b6  {S:d4d5}{W:214Ib}5. d4-d5?. Here Black exchanges pawns {S:e6d5}{W:214Ic}(5... e6xd5  {S:c4d5}{W:214Id}6. c4xd5) and then attacks the d-pawn by completing the fianchetto {S:c8b7}{W:214Ie}(6... Bc8-b7). If White now guards his d-pawn by {S:b1c3}{W:214If}7. Nb1-c3, Black should move his dark-square bishop for a second time {S:e7b4}{W:214Ig}(7... Be7-b4), pinning the c3-knight and forcing the subsequent gain of White's d-pawn. Note that White can't uphold the d-pawn by {S:e2e4}{W:214Ih}8. e2-e4 because, with the c3-knight pinned, Black's f6-knight can take the {A:Bf6e4}{N1:e4}{W:214Ii}e4-pawn for free. Black can also win the e-pawn by first taking on c3 {R}{C}{S:b4c3}{W:214Ij}(8... Bb4xc3+), and after {S:b2c3}{W:214Ik}9. b2xc3, simply removing the unguarded king-pawn {S:f6e4}{W:214Il}(9... Nf6xe4).}]

15.
[{F:B}{B:rnbqkb1r/pppp1ppp/8/4P3/6n1/7P/PPPNPPP1/R1BQKBNR}
{QB:215. After 1. d4 Nf6  2. Nd2 e5  3. dxe5 Ng4  4. h3, where should Black move his attacked knight?{W:215}{A:Bg4e5}{H1:e5}{W:215a}{A:Bg4e3}{H1:e3}{W:215b};4... Nxe5;{F:B}{B:rnbqkb1r/pppp1ppp/8/4P3/6n1/7P/PPPNPPP1/R1BQKBNR}{S:g4e5}{W:215I}Incorrect. The capture of the e5-pawn does not go far enough. It's what might be called a sin of omission, since it fails to exploit White's last error {N1:h3}{W:215Ia}(4. h2-h3?). Other than this, 4... Ng4xe5 is not a bad move. It reestablishes material equality and leaves Black with a splendid game. But a splendid game is not a winning one, so capturing the pawn on e5 must be considered a mistake itself.;4... Ne3;{F:B}{B:rnbqkb1r/pppp1ppp/8/4P3/6n1/7P/PPPNPPP1/R1BQKBNR}{S:g4e3}{W:215C}Correct. White has to go all the way and play 4... Ng4-e3!,  attacking and threatening to win White's queen{A:Be3d1}{W:215Ca}. If the f-pawn doesn't take the knight, White's queen is lost (5... Ne3xd1). If the f-pawn does take White's invasive knight {R}{S:f2e3}{W:215Cb}(5. f2xe3), Black scores with the decisive check, {S:d8h4}{W:215Cc}5... Qd8-h4+. White can delay the inevitable for one move {S:g2g3}{W:215Cd}(6. g2-g3), but Black takes the g-pawn {S:h4g3}{W:215Ce}(6... Qh4xg3#), and this is mate. White's problems ensue from his fourth move, {F:B}{B:rnbqkb1r/pppp1ppp/8/4P3/6n1/7P/PPPNPPP1/R1BQKBNR}{W:215Cf}4. h2-h3?, a move he doesn't have to play. This advance weakens the square {N1:g3}{W:215Cg}g3, which is suddenly deprived of the h-pawn's protection. By moving the knight to e3, Black tries to lure away the g3-square's other pawn protector, {N1:f2}{W:215Ch}the f2-pawn. White finds himself on the horns of a dilemma. Either he gets mated or he loses his queen, all because of a needlessly weakening pawn move. How should White avoid all this? He can use his fourth move more productively, improving his position with {F:B}{B:rnbqkb1r/pppp1ppp/8/4P3/6n1/8/PPPNPPPP/R1BQKBNR}{S:g1f3}{W:215Ci}4. Ng1-f3, developing a new piece toward the center and guarding {N1:h4}{W:215Cj}h4. This stops the potential intrusion of Black's queen, which means that White is not about to get mated.}]

16.
[{F:B}{B:rnbqkb1r/ppp2ppp/4pn2/3P4/8/2N2N2/PP1PPPPP/R1BQKB1R}
{QB:216. After 1. c4 Nf6  2. Nc3 e6  3. Nf3 d5  4. cxd5, how should Black recapture?{W:216}{A:Bf6d5}{H1:d5}{W:216a}{A:Be6d5}{W:216b};4... Nxd5;{F:B}{B:rnbqkb1r/ppp2ppp/4pn2/3P4/8/2N2N2/PP1PPPPP/R1BQKB1R}{S:f6d5}{W:216I}Incorrect. Not with the knight, 4... Nf6xd5. This way of recapturing transgresses the principle that advocates taking with the least valuable unit (here, the pawn). Typically, when you break a rule without a good reason there's a price to be paid. The penalty in the given situation is that White gets to usurp the center by {S:e2e4}{W:216Ia}5. e2-e4!. Black can save his knight without losing time by trading on c3 {S:d5c3}{W:216Ib}(5... Nd5xc3 {S:b2c3}{W:216Ic}6. b2xc3), but even after the thrust {S:c7c5}{W:216Id}6... c7-c5, White is still able to create an ideal pawn center with {S:d2d4}{W:216Ie}7. d2-d4. His two central pawns, aligned and ready for action, insure that White has a definite advantage which he can maintain into the middlegame.;4... exd5;{F:B}{B:rnbqkb1r/ppp2ppp/4pn2/3P4/8/2N2N2/PP1PPPPP/R1BQKB1R}{S:e6d5}{W:216C}Correct. The right recapture is with the pawn, 4... e6xd5. This guarantees that Black keeps a pawn in the center, and it's this pawn that gives Black the opportunity to contest the {N1:e4}{W:216Ca}e4-square. Moreover, by taking with the e-pawn, Black clears the {N1:c8d7e6f5g4h3}{W:216Cb}c8-h3 diagonal for the queen-bishop. If White now advances his queen-pawn two squares ahead {C}{S:d2d4}{W:216Cc}(5. d2-d4), he halts the possible march of Black's d-pawn and transposes into a Queen's Gambit (1. d2-d4 d7-d5 2. c2-c4). This is fine for Black, who can further augment the pressure on e4 by developing the queen-bishop to {S:c8f5}{W:216Cd}f5 and, after {S:e8g8}{S:h8f8}{W:216Ce}castling, by moving the king-rook to {S:f8e8}{W:216Cf}e8.}]

17.
[{F:B}{B:rnbqkb1r/pp1p1ppp/2p2n2/4p3/2P5/2N2NP1/PP1PPP1P/R1BQKB1R}
{QB:217. After 1. c4 Nf6  2. Nc3 e5  3. g3 c6  4. Nf3, should Black push his king-pawn or defend it?{W:217}{A:Be5e4}{H1:e4}{W:217a}{A:Bd7d6}{H1:d6}{W:217b};4... e4;{F:B}{B:rnbqkb1r/pp1p1ppp/2p2n2/4p3/2P5/2N2NP1/PP1PPP1P/R1BQKB1R}{S:e5e4}{W:217C}Correct. It's largely a matter of style and temperament, but we prefer 4... e5-e4, saving the pawn and attacking the {A:Be4f3}{N1:f3}{W:217Ca}f3-knight. Aggression should count for something. By advancing the e-pawn to e4, Black picks up the game's tempo and gathers space in the middle. The White knight is likely to relocate to {R}{C}{S:f3d4}{W:217Cb}d4, where it can be attacked again by either the queen from {S:d8b6}{A:Bb6d4}{N1:d4}{W:217Cc}b6 or the king-bishop from {R}{S:b6d8}{S:f8c5}{A:Bc5d4}{W:217Cd}c5. Crucial for Black is that his e4-pawn can be supported by his queen-pawn. This is made possible by his third move, {F:B}{B:rnbqkb1r/pp1p1ppp/2p2n2/4p3/2P5/2N3P1/PP1PPP1P/R1BQKBNR}{W:217Ce}3... c7-c6, which bolsters the subsequent advance {S:d7d5}{W:217Cf}d7-d5. If after the pawn comes to d5 White should take the d-pawn {S:c4d5}{W:217Cg}(c4xd5), Black's c-pawn is in position to take back {S:c6d5}{W:217Ch}(c6xd5), keeping the pawn chain intact.;4... d6;{F:B}{B:rnbqkb1r/pp1p1ppp/2p2n2/4p3/2P5/2N2NP1/PP1PPP1P/R1BQKB1R}{S:d7d6}{W:217I}Incorrect. Steady defense for the e-pawn can be provided by 4... d7-d6. In its own way it's probably just as good as the alternative, {A:Be5e4}{W:217Ia}4... e5-e4, but it's more defensive in character and outlook. After this one-square advance of the queen-pawn, Black plans to develop the king-bishop to {R}{A:f8e7}{W:217Ib}e7 and then castle. As long as White undertakes no offensive action in the center, Black will encounter few problems. But if White should become active with d2-d4, Black will have to reconsider his strategy. He may have to play the move e5-e4 after all.}]

18.
[{F:B}{B:r1bqkb1r/pp1ppppp/2n2n2/2p5/2PP4/2N2N2/PP2PPPP/R1BQKB1R}
{QB:218. After 1. c4 c5  2. Nc3 Nf6  3. Nf3 Nc6  4. d4, should Black exchange or defend?{W:218}{A:Bc5d4}{H1:d4}{W:218a}{A:Be7e6}{H1:e6}{W:218b};4... c5xd4;{F:B}{B:r1bqkb1r/pp1ppppp/2n2n2/2p5/2PP4/2N2N2/PP2PPPP/R1BQKB1R}{S:c5d4}{W:218C}Correct. The capture 4... c5xd4 is right on the money. Black not only saves his pawn, but he prevents the White d-pawn from advancing menacingly up the board, where it would attack and dislodge Black's {N1:c6}{W:218Ca}c6-knight. Black must understand why he played the move 1... c7-c5 in the first place. Its purpose was to exercise pawn control over the {N1:d4}{W:218Cb}d4-square. This implies that when White puts something on d4, the c5-pawn is supposed to take it. Since exchanging on d4 enables Black to garner a central pawn majority of two-to-one {N1:d4e7}{W:218Cc}(d-pawn and e-pawn vs. {N1:e2}{W:218Cd}e-pawn), and since such a majority is usually advantageous, it's quite illogical to defend the c-pawn by 4... e7-e6 instead of exchanging it for White's d-pawn.;4... e6;{F:B}{B:r1bqkb1r/pp1ppppp/2n2n2/2p5/2PP4/2N2N2/PP2PPPP/R1BQKB1R}{S:e7e6}{W:218I}Incorrect. The weaker move is 4... e7-e6. Its immediate intention is to answer the capture {S:d4c5}{W:218Ia}5. d4xc5 with the recapture {S:f8c5}{W:218Ib}5... Bf8xc5, retaining  material equality. Black also hopes to advance the queen-pawn to d5 sometime later. But neither of these ideas come to fruition, for White crosses them up by crossing midfield, {F:B}{B:r1bqkb1r/pp1p1ppp/2n1pn2/2p5/2PP4/2N2N2/PP2PPPP/R1BQKB1R}{S:d4d5}{W:218Ic}5. d4-d5!. This advance menaces the c6-knight. It also blocks the {N1:d5}{W:218Id}d5-square so that Black is unable to advance his queen-pawn two squares ahead. If Black tries to get rid of this pernicious d-pawn {C}{S:e6d5}{W:218Ie}(5... e6xd5), White's c-pawn is in position to take back {S:c4d5}{W:218If}(6. c4xd5). At the end of this transaction, Black still has to remove his {N1:c6}{W:218Ig}c6-knight to some useless square, forfeiting both time and position. How could Black have avoided all this? By taking White's d-pawn on move four, {F:B}{B:r1bqkb1r/pp1ppppp/2n2n2/2p5/2PP4/2N2N2/PP2PPPP/R1BQKB1R}{S:c5d4}{W:218Ih}4... c5xd4.}]

19.
[{F:B}{B:rnbqkb1r/ppp1pppp/5n2/8/2B5/4PN2/PP1P1PPP/RNBQK2R}
{QB:219. After 1. Nf3 d5  2. c4 dxc4  3. e3 Nf6  4. Bxc4, should Black pin the f3-knight or develop the f8-bishop?{W:219}{A:Bc8g4}{H1:g4}{W:219a}{A:Be7e6}{H1:e6}{W:219b};4... Bg4;{F:B}{B:rnbqkb1r/ppp1pppp/5n2/8/2B5/4PN2/PP1P1PPP/RNBQK2R}{S:c8g4}{W:219I}Incorrect. Do not play 4... Bc8-g4 here. It's a mistake which loses material. White can demonstrate its erroneousness in two different ways. First there's moving the queen to b3 {S:d1b3}{W:219Ia}(5. Qd1-b3), which issues a double attack to {A:Wb3b7}{A:Wc4f7}{N1:b7f7}{W:219Ib}b7 and f7. Black can save one or the other but not both. {R}{C}{S:b3d1}{W:219Ic}Second, there's a combination starting with a temporary bishop sacrifice on f7 {S:c4f7}{W:219Id}(5. Bc4xf7+), which sets up a knight fork at {N1:e5}{W:219Ie}e5. If Black takes the offered bishop {C}{S:e8f7}{W:219If}(5... Ke8xf7), White unpins with {S:f3e5}{W:219Ig}6. Nf3-e5+. Black must move his king out of check {S:f7e8}{W:219Ih}(6... Kf7-e8), whereupon White's e5-knight takes the g4-bishop {S:e5g4}{W:219Ii}(7. Ne5xg4). Even if Black takes back {S:f6g4}{W:219Ij}(7... Nf6xg4), White's queen is there to finish off the combination {S:d1g4}{W:219Ik}(8. Qd1xg4), regaining the piece and leaving White a pawn ahead. So White emerges from the combination with both a material plus, as well as a positional one, especially because Black's king has lost the castling privilege.;4... e6;{F:B}{B:rnbqkb1r/ppp1pppp/5n2/8/2B5/4PN2/PP1P1PPP/RNBQK2R}{S:e7e6}{W:219C}Correct. The alert move is 4... e7-e6. True, this advance closes the {N1:c8d7e6f5g4h3}{W:219Ca}c8-h3 diagonal, locking his own queen-bishop inside the pawn chain. But more importantly it obstructs the attacking diagonal of White's {N1:c4}{W:219Cb}c4-bishop, stopping once and for all any shots to the {N1:f7}{W:219Cc}f7-square. The move e7-e6 also has its offensive side, for with the {N1:a3b4c5d6e7f8}{W:219Cd}a3-f8 diagonal unblocked, the dark-square bishop is empowered to support the advance {S:c7c5}{W:219Ce}c7-c5. This counterattack would pressure d4. As for some of the other Black pieces, the king-bishop will probably go to {C}{A:Bf8e7}{W:219Cf}e7. Black will then castle kingside. Eventually he will flank his queen-bishop on {A:Bc8b7}{W:219Cg}b7. At this point Black will have a better idea what to do with the rest of his life.}]

20.
[{F:B}{B:rnbqk2r/ppppppbp/5np1/16/5NP1/PPPPPPBP/RNBQ1RK1}
{QB:220. After 1. Nf3 Nf6  2. g3 g6  3. Bg2 Bg7  4. 0-0, should Black maintain the symmetry or create imbalance?{W:220}{A:Bh8f8}{A:Be8g8}{H1:f8g8}{W:220a}{A:Bb7b5}{H1:b5}{W:220b};4... 0-0;{F:B}{B:rnbqk2r/ppppppbp/5np1/16/5NP1/PPPPPPBP/RNBQ1RK1}{S:h8f8}{S:e8g8}{W:220C}Correct. Black is free to castle, and he should do it right here on move four (4... 0-0). There's no inherent value in keeping the Black king at e8, and since White knows that castling is high on his opponent's agenda, why shouldn't Black play it at once? Castling offers a number of benefits while revealing very little information. What White doesn't know much about, however, is how Black intends to arrange his center pawns. Three options come to mind. Black could advance the c-pawn to {A:Bc7c5}{W:220Ca}c5. He could advance the d-pawn to {R}{A:Bd7d5}{W:220Cb}d5. Or he could move the d-pawn just to {R}{A:Bd7d6}{W:220Cc}d6, with the idea of backing up the king-pawn's subsequent advance to {A:Be7e5}{W:220Cd}e5. All of these aims are quite reasonable, and to be expected. But, as already indicated, Black's real secret is what he intends to do with his center pawns. By castling on move four he keeps White guessing and maintains the greatest freedom of choice.;4... b5;{F:B}{B:rnbqk2r/ppppppbp/5np1/16/5NP1/PPPPPPBP/RNBQ1RK1}{S:b7b5}{W:220I}Incorrect. Black's leeway does not extend to 4... b7-b5, which is a bad move. The plan is to oppose White's flanked bishop at {N1:g2}{W:220Ia}g2 by flanking his own queen-bishop at {A:Bc8b7}{W:220Ib}b7. But White's bishop is already in place and he is the first to strike. White unmasks the g2-bishop by {R}{C}{S:f3d4}{W:220Ic}5. Nf3-d4!. This attacks the {A:Wg2a8}{N1:a8}{W:220Id}a8-rook, while the d4-knight additionally threatens the {R}{C}{A:Wd4b5}{N1:b5}{W:220Ie}b5-pawn. Black could try to save both by {R}{C}{S:c7c6}{W:220If}5... c7-c6, but this fails to {S:d4b5}{W:220Ig}6. Nd4xb5!. White is able to take this apparently protected b-pawn because the defender (the c6-pawn) is pinned to the a8-rook by the {A:Wg2c6}{W:220Ih}g2-bishop. So the net result of the advance of the b-pawn to b5 is that it drops a pawn.}]