qa4 การใช้

• Rc1 Re8 18 . g4 Qf6 19 . Qa4 Qe7 20.
• 34 . . . Rb1 . . . . Qa4
• Qa4 . . . . . . Bc6
• Usually, white will recover the pawn with Qc2 and a4, Ne5, or Qa4.
• The obvious response to this from white would be Qa4, which both checks me and threatens my bishop.
• Nc6 4 . Qa4; as well as the Ponziani and Center Game openings, to name just a few.
• Nc3 d5 4 . d4 c6 5 . e3 a6 6 . c5 Nbd7 7 . b4 a5 8 . b5 e5 9 . Qa4 Qc7 10.
• Earl Sacerdoti and Rene Reboh developed QLISP, an extension of QA4 embedded in INTERLISP, providing Planner-like reasoning embedded in a procedural language and developed in its rich programming environment.
• Soon, after 16 Qa4, it looked unsafe for either player to castle on the king's wing, and it was against the rules to do so on the other flank.
• At SRI International, Jeff Rulifson, Jan Derksen, and Richard Waldinger developed QA4 which built on the constructs in Planner and introduced a context mechanism to provide modularity for expressions in the database.
• On 21 . . . Ra8, Anand could not achieve anything with 22 e5 de 23 fe Nd5 24 Bd5 ed 25 Qd5 Qc2 26 Rb7 Qa4, but he kept up the attack with 22 c4.
• Khalifman put his trust in a simplifying exchange with 10 . . . Ba4 11 Qa4, but maybe he should have avoided loosening his queenside with 11 . . . b5 in favor of 11 . . . Qd7.
• Deep Blue's 23 . . . c5 was energetic, yet after 24 Nf3 Rd1 25 Rd1 Nc4 26 Qa4 Rd8 27 Re1 Nb6 28 Qc2 Qd6, Kasparov cut down the scope of the b6 knight by 29 c4.
• Romanishin's clever 25 . . . Rab8 looked toward 26 Ra6 Ra8 ! 27 Ra8 Ra8 28 Nb6 Ra3 or 26 Rd6 Ba4 ! 27 Qa4 Rb2 ! 28 Rf2 Rb1 29 Rf1 Rb2 with a draw by repetition of the position.
• If Black takes the pawn, then in the same manner as the QGA, 3 . e3 or 3 . e4 regain the pawn with a slight advantage to White Black being left somewhat undeveloped . 3 . Na3 and 3 . Qa4 + are also good, and commonly played.
• Thus, 5 Qa4 may leave the queen misplaced later, 5 Qc2 invites 5 . . . c5, when 6 d5 ? ! leads to a dubious gambit after 6 . . . ed 7 cd Bb7 8 e4 Qe7 9 Nc3 Nd5 and 5 Nd2 diverts the queen knight from its most effective post, c3.
• A rare variant has also occurred in a miniature in the Fajarowicz variation, after the moves 1 . d4 Nf6 2 . c4 e5 3 . dxe5 Ne4 4 . Qc2 Bb4 + 5 . Nd2 d5 6 . exd6 Bf5 7 . Qa4 + Nc6 8 . a3 Nc5 9 . dxc7 Qe7 ! when White, trying to save his queen, fell into 10 . Qd1 Nd3 mate.
• This gives white four choices : 5 Qa4, when the queen may be left out of action; 5 Qc2, when 5 . . . c5 6 d5 ? ! is dubious after 6 . . . ed 7 cd Bb7 8 e4 Qe7 9 Nc3 Nd5; 5 Nd2, when this knight has less scope than at c3, or the solid 5 b3, which Karpov also uses when he has white.
• 1 . d4 d5 2 . a3 Nf6 3 . Nf3 Nbd7 4 . Bf4 g6 5 . h3 Bg7 6 . e3 0 0 7 . Nbd2 b6 8 . c3 Bb7 9 . Qb3 Ne4 10 . Rd1 Nxd2 11 . Rxd2 e5 12 . dxe5 Qe7 13 . Be2 Nxe5 14 . Nxe5 Bxe5 15 . Bxe5 Qxe5 16.0 0 Rfd8 17 . Rfd1 Rd6 18 . Bf3 Rad8 19 . Qa4 a5 20 . c4 c6 21 . cxd5 cxd5
• :1 . e4 e5 2 . Nf3 Nc6 3 . Bc4 Bc5 4 . b4 Bxb4 5 . c3 Ba5 6 . O-O Qf6 7 . d4 h6 8 . Qa4 Bb6 9 . Bb5 Nge7 10 . Ba3 exd4 11 . e5 Qg6 12 . cxd4 Nd5 13 . Re1 Nf4 14 . g3 Qg4 15 . Nbd2 Nh3 + 16 . Kg2 Ng5 17 . Bb2 Ne7 18 . Be2 Ne6 19 . Kh1 Qf5 20 . Nh4 Qxf2 21 . Ne4 ( 1-0)