(;
GM[1]
SZ[19]
AW[bb][cb][db][dc][ed][fc][dh][cl][cr][dq][eq][gq][jq][nc][qj][qm]
AB[cc][bc][ad][be][ce][de][dd][df][ec][bq][cq][dp][co][fo][oq][qp][pd][qf]
LB[nc:A][qf:B][qm:C]
C[Problem 120. Black to play.  

White has played the sequence to C on the right side. How should Black continue ?  

[You will find a supplement to this Problem Diagram as "Problem 147"] ]
;B[cj]
TE[2]
C[Correct Answer.  

On the left side, Black is strong above and below, while White's two stones are thin. Therefore, Black should invade at 1. Next ... ]
;W[dj]
C[If White attaches with 2, ... ]
(;B[ci];W[di];B[ch]
LB[ci:3]
C[... Black can link up with his stones at the top with 3 and 5. White's stones are still without eye shape. <= ]
)
(;B[di]
C[Failure.  

Wedging in with Black 3 is not good in this position. ]
;W[ci]
C[White can now secure her stones on the left side by playing 4 ... ]
;B[ei];W[bj]
C[... and 6. <= ]
)
)