EVENT
BOARDSIZE 19
SETUP W C17 D16 D14 D4 R11 P11 Q7 R6 Q5 
SETUP B D18 F17 J17 Q16 R13 R5 R4 Q3 O3 
MARK \t@P11
COM
Problem 73. Black to play.  

When White jumps into the center with the marked stone, the skirmish
on the right side comes to a pause. Where should Black play next
? 
ENDCOM
B 1 C9
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Black should break up White's position on the left with 1.
ENDCOM
W 2 C11
COM
If White next plays 2, ...
ENDCOM
  VAR
  W 2 C7
  COM
  Variation.

  If White 2 here, ...
  ENDCOM
  B 3 C12
  MARK 1@C9
  COM
  ... Black will extend to 3. No matter how White attacks, Black
  can easily settle his stones on the left side, so Black 1 is
  the perfect point to play.
  <=
  ENDCOM
  ENDVAR
B 3 C6
COM
... Black can extend to 3.
ENDCOM
W 4 C5
COM
After the exchange of White 4 ...
ENDCOM
B 5 D6
COM
... for Black 5, ...
ENDCOM
W 6 F4
MARK A@F3
COM
... White will play either 6 or A.
<=
ENDCOM