EVENT
BOARDSIZE 19
SETUP W B18 C18 D18 D17 E16 F17 D12 C8 C2 D3 E3 G3 K3 O17 R10 R7 
SETUP B C17 B17 A16 B15 C15 D15 D16 D14 E17 B3 C3 D4 C5 F5 P3 R4 Q16 R14 
MARK A@O17 B@R14 C@R7
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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"]
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B 1 C10
USER
CORRECT ANSWER
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COM
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
...
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W 2 D10
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If White attaches with 2, ...
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B 3 C11
  VAR
  B 3 D11
  COM
  Failure.

  Wedging in with Black 3 is not good in this position.
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  W 4 C11
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  White can now secure her stones on the left side by playing 4
  ...
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  B 5 E11
  W 6 B10
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  ... and 6.
  <=
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  ENDVAR
W 4 D11
B 5 C12
MARK 3@C11
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... Black can link up with his stones at the top with 3 and 5.
White's stones are still without eye shape.
<=
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