(;
GM[1]
SZ[19]
AW[cn][fm][dg][gg][hd]
AB[jp][jd][pj][dj][dp][pd][pp][dd][fd][fj][hj][fp]
LB[cn:1][fp:2][dg:3][fd:4][fm:5][fj:6][gg:7][hj:8][hd:9]
C[Problem 15. Black to play.  

White invades the top with 9, isolating the two black stones and hoping to start a fight around here. How should Black respond ? ]
(;B[ig]
TE[2]
C[Correct Answer.  

Black 1 is a severe attack. Besides mapping out a large moyo in the upper right, it threatens to split White's overstretched stones. ]
;W[hf]
C[White 2 ensues a connection between her stones, but ... ]
(;B[ce]
C[... Black 3 robs them of their base white securing the territory in the corner. <= ]
;W[if])
(;B[if]
C[If Black wants to emphasise his moyo, he will block with 3. ]
;W[cd]
C[White would then attach at 4. <= ]
))
(;B[fb]
LB[cd:A]
C[How the game continued.  

Black defended the corner with 1, but this move was off the mark. White's stones on the left could still make a base by attaching at A. ]
;W[nd]
C[White switched to the upper right with 2, putting pressure on the two black stones at the top. ]
;B[ld]
C[Black tries to alleviate this pressure by making a checking extension to 3, but ... ]
;W[nf]
C[... after exchanging 4 ... ]
;B[pf]
C[... for 5, ... ]
;W[jh]
C[... White attacked on a large scale with 6. See Problem 19 for the continuation of this game. <= ]
)
)