(;
GM[1]
SZ[19]
AW[dd][fd][ic][dp][kq][nq][pr][md][nc][oc][of][ng][pg][qf]
AB[cf][ci][qq][pp][pn][qj][pj][pd][pc][pe][nd][ne][pf]
TR[ng][of][pg][qf]
C[Problem 34. Black to play.  

How should Black attack the marked white stones ? ]
;B[oh]
TE[2]
C[Correct Answer.  

Black first peeps with 1, ... ]
;W[og]
(;B[ld]
C[... then attacks the three white stones at the top with the clamp of 3. ]
(;W[me]
C[If White extends to 4, ... ]
;B[mc]
C[... Black cuts at 5. If White ... ]
;W[lc];B[mb];W[lb];B[mf];W[le];B[lf];W[ke]
C[... insists on saving her stones at the top with the sequence to 12, ]
;B[mh]
C[... Black casts a net with 13, ... ]
;W[mg];B[lg];W[nh];B[ni]
C[... trapping the white stones on the right. ]
;W[oi]
C[If White cuts at 18, ... ]
;B[nj]
C[... Black extends at 19 and White's stones can't get two eyes. <= ]
)
(;W[lc]
TR[ld]
C[Variation.  

If White answers the marked stone with 4, ... ]
;B[me]
C[... Black presses along the top with 6 ... ]
;W[mc];B[kd]
C[... and 8. ]
;W[kc];B[mh]
C[He then casts a net with 9, trapping the white stones. <= ]
))
(;B[mf]
C[Failure.  

Black 3 aims at both the white stones at the top and on the right, but it lacks in severity. ]
;W[nh];B[nj];W[lh];B[mc]
C[When Black cuts at 7, ... ]
;W[mb]
C[... White can live at the top with 8 ... ]
;B[lc];W[lb]
C[... and 10. White's stones are now safe. <= ]
)
)