(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]
RU[Japanese]SZ[19]KM[0.00]
GN[ ]PW[ ]PB[Black to play and kill]AW[nq][oq][pq][qq][rq]AB[mo][oo][qo][np][rp][mq][mr]C[Having solved problem 4, the trick here is to reduce White to the same shape.]FG[259:]PM[2]
;B[os]
;W[ps]
;B[ns]
(;W[or]C[This is the same as problem 4 so Black knows how to kill.])
(;W[rs]C[White can try this play instead.]
;B[sr]C[This the play that kills this shape.]
;W[sq]
;B[pr]
;W[qr]
;B[or]C[Dead.])
(;W[pr]C[White can also try this.]
;B[sq]
;W[sr]
;B[rs]C[Also dead])
(;W[qr]C[And this.]
;B[or]
;W[rs]
;B[sr]
;W[sq]
;B[pr]C[It is also dead.]))
