(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]
RU[Japanese]SZ[19]KM[0.00]
PB[Black to play and kill]AW[om][pm][mn][nn][on][po][qo][mp][op][mq][nq][oq][rq][pr][qr][rr]AB[nl][ol][pl][rl][mm][qm][ln][rn][lo][ro][lp][pp][qp][sp][lq][sq][mr][nr][sr][os][ps][qs][rs]
(;B[no]C[If white plays here the group lives so black must play here first.]
;W[mo]
(;B[oo]C[Sacrificing a second stones is the next skilful play.]
;W[np]
(;B[oo]C[And then the throw in]
(;W[no]
;B[qn]C[After this white can only get one eye.]
(;W[pn]
;B[rp])
(;W[rp]
;B[pn]
;W[oo]))
(;W[rp]
;B[pn]C[White gets caught in a snapback shape this way too.]))
(;B[rp]C[This is wrong.]
;W[qn]))
(;B[qn]C[This is wrong.]
;W[rp]))
(;B[rp]
;W[no]
;B[qn]
;W[pn]C[White lives easily if black saves the two stones. ])
(;B[qn]
;W[rp]
;B[no]
;W[mo]C[This is no good.]))
