(;AB[cr]AB[dr]AB[es]AB[bq]AB[bp]AW[bo]AW[co]AW[cq]AW[dq]AW[er]AW[fr]AW[eo]LB[bs:a]LB[ar:b]LB[ds:c]LB[br:e]LB[ap:d]AW[ss]AW[rs]AW[sr]AW[rq]AW[qr]AW[qs]AW[pq]AW[or]AW[os]AW[ps]AB[ns]AB[nr]AB[nq]AB[oq]AB[op]AB[pp]AB[qp]AB[rp]AB[sp]AB[sq]AB[qq]AW[so]AW[ro]AW[qo]AW[po]AW[oo]AW[no]AW[np]AW[mp]AW[mq]AW[lq]AW[lr]AW[ls]LB[bp:E]LB[bq:E]LB[cr:E]LB[dr:E]LB[es:E]C[Help the marked stones E.]AP[goproblems]
(;B[bs];W[ar]LB[ds:a]LB[br:b]LB[aq:c]LB[ap:d]
(;B[ds];W[br];B[aq]C[Black has enough liberties to play here in this case(marked E)RIGHT]LB[aq:E]LB[bq:E]LB[bp:E]LB[bs:E]LB[cr:E]LB[dr:E]LB[ds:E]LB[es:E];W[mr]LB[pr:a]LB[rr:b]LB[ns:E]LB[nr:E]LB[nq:E]LB[oq:E]LB[op:E]LB[pp:E]LB[qp:E]LB[qq:E]LB[rp:E]LB[sp:E]LB[sq:E]C[Help the marked stones E.]
(;B[pr];W[ms];B[rr]C[RIGHT])
(;B[rr];W[ms];B[pr]C[RIGHT]))
(;B[br];W[ds])
(;B[aq];W[ds])
(;B[ap];W[ao]LB[ds:a]LB[br:b]
(;B[ds];W[br]LB[aq:a]LB[as:b]
(;B[aq];W[cp])
(;B[as];W[cs]))
(;B[br];W[ds])))
(;B[ar];W[bs]LB[ap:a]LB[br:b]
(;B[ap];W[br]LB[cs:a]LB[as:b]LB[ao:c]
(;B[cs];W[ds])
(;B[as];W[aq])
(;B[ao];W[bm]))
(;B[br];W[ap]))
(;B[ds];W[bs]C[Even if black plays at A now, it will almost never be sente, because B and C are miai.]LB[br:A]LB[ap:B]LB[ar:C])
(;B[ap];W[ar]LB[br:A]LB[bs:C]LB[ds:B]C[Even if black plays at A now, it will almost never be sente, because B and C are miai.])
(;B[br];W[ap]LB[aq:a]LB[ds:b]
(;B[aq];W[ds];B[cs];W[as];B[ao];W[bm])
(;B[ds];W[aq];B[ar];W[bs]LB[fs:a]LB[ao:b];B[fs]C[Some players worry that black can escape like this. However, unless there's a stone nearby on the bottom side, there's no way to escape. For example...];W[gr];B[gs]LB[ir:a]LB[hr:b]
(;W[ir];B[hs];W[jq];B[hr];W[hq]LB[gq:a]LB[eq:b]
(;B[gq];W[gp]LB[fq:a]LB[eq:b]
(;B[fq];W[eq];B[fp];W[fo])
(;B[eq];W[fq];B[ep]))
(;B[eq];W[fq];B[ep];W[fp];B[dp];W[cp]))
(;W[hr];B[hs];W[ir]C[White will make as many of these exchanges as black likes.]))))