(;GM[1]
FF[4]
AP[Hibiscus:2.1]
SZ[19]
ST[3]
;C[Black has played an irregular
enclosure at the top. If he is allowed to
play at A, it will almost be a fortress.
How to prevent this from happening?]
PL[W]
LB[yy:1][oe:A][pd:B][qc:C]AB[oc][pp][qe]
AW[dd][dp]
(;W[pd]
MN[1]
;B[oe]
(;W[od]
;B[nd]
;W[pe]
;B[pf]
;W[qc]
;B[of]
;W[nc]
;B[mc]
;W[nb]
;B[md]
;W[ob]
C[RIGHT]
)(;W[pe]
;B[pf]
;W[od]
;B[nd]
;W[qc]
;B[of]
;W[nc]
;B[mc]
;W[nb]
;B[md]
;W[ob]
C[RIGHT]
))(;W[oe]
;B[pd]
C[White achieves nothing]
)(;W[qc]
;B[pd]
C[You might be able to make live here
but it will surely be profitable for Black.]
))