(;
GM[1]
SZ[19]
AW[bc][cd][ce][ic][oq][qr][np][bp][cn][dl][ci]
AB[dp][pd][dd][cc][cb][ec][qj][qp][pn][kp][fp][cq]
C[Problem 140. Black to play.  

In this two-stone handicap game, it is Black's turn to play. How should he attack the lone white stone at the top ? ]
(;B[de]
TE[2]
C[Correct Answer.  

Black must first press White against the left side with 1 ... ]
;W[df];B[ef]
C[... and 3. ]
;W[dg];B[kc]
C[Now he can pincer with 5. ]
;W[ie]
C[If White jumps to 6, ... ]
;B[ke]
C[... Black keeps up the pressure with 7. A large-scale black moyo is beginning to take shape on the right side. <= ]
)
(;B[kc]
C[Failure.  

If Black pincers at 1 without making any preparatory moves on the left, ... ]
;W[ef]
C[... White will reach out to her stone with the knight's move 2. <= ]
)
(;B[ef]
C[Failure.  

The knight's move of Black 1 is not forceful enough. ]
;W[lc]
C[White can take up a position at the top with 2 and Black has lost the initiative here. <= ]
)
)