EVENT
BOARDSIZE 19
SETUP W O17 K16 D16 D10 D6 D4 C3 C2 
SETUP B E3 D3 F4 K4 Q4 Q10 Q16 Q14 
COM
Problem 34. Black to play.  

Both sides have occupied all the star points. Where should Black
play next ? 
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B 1 F6
MARK B@D8 A@H4
USER
CORRECT ANSWER
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COM
Correct Answer.

White A is a good invasion point, so Black should defend by jumping
to 1, expanding his moyo at the expense of White's, and aim to
invade at B.
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  VAR
  B 1 N15
  COM
  Failure.

  If Black plays 1 in the upper right, ...
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  W 2 F6
  COM
  ... then White 2 ...
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  B 3 H4
  COM
  ... would force Black to defend at 3.
  <=
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  ENDVAR
  VAR
  B 1 Q6
  COM
  Failure.

  If Black 1 here, ...
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  W 2 F6
  MARK A@G6
  COM
  ... White will jump to 2 or A.
  <=
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  ENDVAR
W 2 D8
COM
White has many ways to respond, but if she defends with 2, ...
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B 3 Q6
MARK A@O4
COM
... Black will strengthen his moyo by 3 or A.
<=
ENDCOM