EVENT
BOARDSIZE 19
SETUP W C10 D16 D4 D6 H4 J3 H3 K3 M3 R11 
SETUP B F3 F5 G5 H5 J4 K4 L4 N5 Q4 Q16 
MARK \t@C10
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Problem 25. Black to play.  

White has just extended along the left side with the marked stone.
What should Black do ? 

[You will find a supplement to this Problem Diagram as "Problem 139"]
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B 1 N2
USER
CORRECT ANSWER
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COM
Correct Answer.

Black should attack the white stones at the bottom with 1.
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W 2 M2
B 3 O3
W 4 G2
B 5 F2
W 6 L3
COM
White can live in the sequence to 6, but Black ends in sente,
so ...
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B 7 Q10
COM
... he can continue by building a moyo in the center by making
a shoulder hit at 7.
<=
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