(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]
RU[Japanese]SZ[19]KM[0.00]
PB[Black to play]AW[op][pp][qp][mq][nq][qq][mr][qr][ms][os]AB[lo][mp][np][lq][oq][pq][lr][nr][pr][ps]C[Black to play and trap some white stones]
(;B[ls]C[This is the move that catches white short of liberties.]
(;W[ns]
;B[or])
(;W[or]
;B[ns])
(;W[qs]
;B[ns]))
(;B[or]C[This catches black short]
;W[qs]
;B[ns]
;W[os])
(;B[ns]
;W[or]))
