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BOARDSIZE 19
SETUP W K17 O16 
SETUP B D16 F17 Q15 R17 R10 
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Problem 11. Black to play.  

Again White has a three-space high extension, but the neighbouring
black stones are on different points. How should Black play ?

<See Reference Diagram 11 for 'White to move' in the upper right.>
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B 1 M17
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CORRECT ANSWER
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COM
Correct Answer.  

Black should make a deep invasion with 1.  
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W 2 M16
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This time, when White attaches with 2, ...  
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B 3 N17
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... Black simply extends to 3, ...  
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W 4 N16
B 5 P18
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... then jumps lightly to 5.  
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W 6 L17
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White must complete her shape with 6, so Black ends in sente.
<= 
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