(;AB[kp]AB[kq]AB[kr]AB[nq]AW[jr]AW[jq]AW[hr]AW[hq]AW[hp]AB[gr]AB[gq]AB[gp]AB[fp]AB[ep]AB[dp]AB[do]AB[en]AB[fn]AW[ho]AW[hn]AW[gm]AW[fm]AW[em]AW[dn]AW[cn]AW[co]AW[cq]AW[br]AW[fq]AW[fr]C[How can Black get life for his cut-off group ?]AP[goproblems]
(;B[es]
(;W[gs];B[fs];W[er];B[hs];W[dr];B[js]C[Black 1 is the tesuji. If 2, Black connects up with his other stones. White 2 at 4 is no good, as Black plays 6if next White 3, then Black 2. RIGHT]LB[es:1]LB[gs:2]LB[fs:3]LB[er:4]LB[hs:5]LB[dr:6]LB[js:7])
(;W[er];B[dr];W[fs];B[gs];W[ds];B[eq]C[RIGHT]))
(;B[fs];W[es];B[gs];W[dr]LB[fs:1]LB[es:2]LB[gs:3]LB[dr:4]LB[er:a]C[(wrong). Black 1 fails, as throwing in at a after 4 does not work. CHOICE])
(;B[hs];W[is]C[]
(;B[er];W[gs]
(;B[eq];W[fs];B[es];W[hs]C[CHOICE])
(;B[es];W[fs];B[eq];W[hs]C[CHOICE]))
(;B[fs];W[es]
(;B[er];W[gs];B[eq];W[fs];B[ds];W[hs]C[CHOICE])
(;B[gs];W[dr];B[eq];W[er]C[CHOICE]))
(;B[es];W[gs]
(;B[fs];W[er]
(;B[dr];W[ds]C[CHOICE])
(;B[hs];W[ds];B[gs];W[dq]C[CHOICE]))
(;B[er];W[fs];B[eq];W[hs]C[CHOICE])
(;B[eq];W[fs];B[er];W[hs]C[CHOICE]))))