EVENT
BOARDSIZE 19
SETUP W D16 F17 L16 R10 R7 D3 F3 C5 C4 
SETUP B Q16 R13 Q4 N3 D5 D6 C6 D10 C14 
COM
Problem 68. Black to play.  

The fuseki is coming to a close, but there are still important
points left. Where is Black's biggest move ? 
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B 1 E14
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Black 1 is the biggest move. If White were to play there, she
would be able to build a moyo at the top.
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  VAR
  B 1 R5
  COM
  Failure.

  Black 1 is certainly a big point, but ...
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  W 2 E14
  COM
  ... White will force with 2, building a moyo at the top, ...
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  B 3 D12
  W 4 O17
  MARK \t@R13
  COM
  ... then approach with 4. Note that the marked black stone is
  two spaces away from the white formation below, so White's stones
  there are not being attacked all that severely.
  <=
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  ENDVAR
W 2 S4
MARK A@R5
COM
White 2 is necessary to prevent Black A, which defends the corner
and attacks the white stones.
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B 3 G16
COM
However, Black will now reduce White's potential territory at
the top with 3 ...
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W 4 G17
B 5 J16
COM
... and 5.
<=
ENDCOM