(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]
RU[Japanese]SZ[19]KM[0.00]
PB[Black to play]AW[po][op][qp][oq][pq][qq][qr][os]AB[pn][qn][no][rp][lq][mq][nq][rq][kr][rr]C[This is the problem position. Black to play]
;B[ps]LB[pr:B][qs:A]C[This is the eye-stealing move.
White dies clearly if he plays A or B.]
(;W[qs]
;B[or]LB[nr:B][pr:A]C[Again a choice of A or B which both fail.]
(;W[pr]
;B[nr]C[False eye.])
(;W[nr]
;B[ns]
;W[pr]
;B[mr]
;W[os]
;B[nr]C[Ditto]))
(;W[pr]C[Black can kill simply if white plays here,
but he can also get it wrong.]
(;B[qs]C[This way is wrong.]
(;W[rs]
(;B[qs]C[Another false eye]
(;W[ps]
;B[nr])
(;W[nr]
;B[mr]C[real eye
]))
(;B[nr]))
(;W[nr]
;B[rs]
;W[mr]
;B[ms]
;W[lr]
;B[ls]
;W[kq]C[Dangerous
]))
(;B[nr]C[This simply kills.]
;W[qs]
;B[or]))
(;W[nr]C[This is whites' strongest reply the following moves
are all forced.]
;B[qs]
;W[mr]
;B[ms]
;W[lr]
;B[ls]
;W[kq]C[If this cut is dangerous, then white may still get away,
though black gained points in the corner. 
If the cut is dangerous then black should protect it
first which would then be sente to kill the white group.]))
