(;SZ[19]AW[qg]AW[qh]AW[qi]AW[pj]AW[pk]AW[pl]AW[sl]AW[pm]AW[qn]AW[rn]AW[ro]AW[rp]AB[qj]AB[qk]AB[ql]AB[qm]AB[rm]AB[pn]AB[po]AB[qp]AB[rq]AB[qr]TR[sl]C[White played T8. How to punish?]GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]RU[Japanese]KM[0.00]PW[tsumego6bis]
(;B[sm];W[rj]
(;B[sp];W[rk]
(;B[so];W[rl]C[Black got tricked])
(;B[sn];W[rl]C[Black got tricked]))
(;B[rk];W[sk];B[ri];W[si]C[Ko is not enough])
(;B[sk];W[rk];B[rl];W[sn]C[Black got tricked])
(;B[ri];W[rk]C[Black is captured])
(;B[qo];W[rk]C[Black is captured]))
(;B[rj]
(;W[sm]C[CHOICE]
(;B[sk];W[sn]
(;B[ri];W[rl]
(;B[sp];W[rk];B[qo];W[sj];B[si];W[rh];B[sk]C[Ko])
(;B[rh];W[rg];B[sp];W[rk]
(;B[si];W[sj]C[Ko, black must win it twice])
(;B[qo];W[sj]C[Black is captured])))
(;B[rl];W[si]
(;B[sp];W[sj];B[qo];W[rk]C[Ko is not enough])
(;B[ri];W[rh]
(;B[sp];W[sh];B[qo]C[CorrectRIGHT])
(;B[qo]C[NOTTHIS])
(;B[so]C[NOTTHIS])))
(;B[sp];W[rl]
(;B[ri];W[rk];B[qo];W[sj];B[si];W[rh];B[sk]C[Ko])
(;B[qo];W[ri];B[sq];W[si];B[so]C[CorrectRIGHT])))
(;B[sn];W[sk]
(;B[sp];W[so];B[sq];W[sn]
(;B[sj];W[ri];B[qo];W[si])
(;B[qo];W[ri];B[sj];W[si]))
(;B[sj];W[ri];B[sp];W[so];B[sq];W[si];B[qo];W[sn]))
(;B[sp];W[sk]C[Seki])
(;B[ri];W[sk];B[rh];W[rg]C[Seki]))
(;W[sj]C[Another possible white defense.]
(;B[si];W[sk];B[sm])
(;B[sm];W[ri];B[sp])))
(;B[sn];W[sm]
(;B[sp];W[so];B[sq];W[sj])
(;B[sk]
(;W[so]C[CHOICE]
(;B[rl];W[rj];B[sn];W[sm];B[ri];W[si];B[qo];W[rh];B[sl];W[sj];B[sn]C[Ko is not enough])
(;B[rj]C[Correct. White loses the semaiRIGHT]))
(;W[rj];B[rl];W[sm];B[ri];W[si];B[sp];W[sj];B[qo]))
(;B[rj];W[sk]
(;B[sp];W[so];B[sq];W[sn]
(;B[sj];W[ri];B[qo];W[si])
(;B[qo];W[ri];B[sj]))
(;B[sj];W[ri];B[sp];W[so];B[sq];W[si];B[qo];W[sn]))
(;B[rk];W[sj]
(;B[sk];W[rj])
(;B[ri];W[sk]))
(;B[qo];W[so]
(;B[rj];W[sk]C[Seki.])
(;B[sk];W[rj]C[Black is captured])
(;B[sq];W[sj]C[Black is captured])))
(;B[sp];W[sm]
(;B[sn];W[so];B[sq];W[sj])
(;B[sk];W[rj])
(;B[rj];W[sk]C[Seki]))
(;B[qo]C[The variations are identical to black T4 first.])
(;B[sk];W[rj]
(;B[ri];W[rk])
(;B[rk];W[ri]C[Black is dead.])
(;B[sn];W[rk]
(;B[sp];W[rl])
(;B[sm];W[so]))
(;B[rl];W[rk];B[sm];W[sn]))
(;B[rk];W[sm]
(;B[sn];W[sj]
(;B[sk];W[rj])
(;B[ri];W[sk]))
(;B[ri];W[sj];B[sk];W[rh]
(;B[si];W[sh];B[rj];W[sn])
(;B[sn];W[so];B[qo];W[si];B[sq];W[rj]))
(;B[sk];W[sj]
(;B[ri];W[rh]
(;B[si];W[sh];B[rj];W[sn])
(;B[sn];W[so];B[qo];W[si];B[sq];W[rj]))
(;B[sn];W[rj])
(;B[si];W[ri];B[rj];W[sn])))
(;B[ri];W[sm]
(;B[rj];W[sk];B[rh];W[rg]C[Seki])
(;B[sn];W[sj]C[At best black will get a seki])
(;B[sj];W[sn]C[At best black will get a seki.])
(;B[rh];W[rj];B[rk];W[sj]C[Black is captured]))
(;B[sj];W[rj]C[Black is captured]))