(;GM[1] FF[4] AP[Hibiscus:2.1] SZ[19] ST[3] ;AB[bl][bn][cn][dn][dq][en][eq][fo][fq][gp][gr] AW[an][bo][br][co][cp][dp][ep] PL[B] C[Black to kill] (;B[ds] (;W[cs] C[Black 1 make a good use of the marked stone.] TR[gr]LB[ds:1](;B[cr] ;W[bs] (;B[ap] ;W[ao] (;B[bq] ;W[cq] (;B[ar] ;W[dr] ;B[es] C[RIGHT Now we can see how the two marked stones works together.] TR[gr][ds])(;B[dr] ;W[bp] C[White lives.] )(;B[aq] ;W[dr] C[White lives.] ))(;B[ar] ;W[bq] C[White lives.] )(;B[cq] ;W[bq] C[White lives.] ))(;B[cq] ;W[bq] C[White lives.] )(;B[bq] ;W[cq] (;B[dr] ;W[aq] C[White lives.] )(;B[ap] ;W[ar] (;B[ao] ;W[bp] (;B[am] ;W[aq] (;B[an] ;W[dr] C[White lives.] )(;B[dr] ;W[an] C[White lives.] ))(;B[dr] ;W[aq] C[White lives.] ))(;B[dr] ;W[ao] C[White lives.] ))(;B[aq] ;W[dr] C[White lives.] )(;B[ar] ;W[dr] C[White lives.] )(;B[ao] ;W[ap] C[White lives.] ))(;B[aq] ;W[cq] (;B[dr] ;W[bq] ;B[ap] ;W[ar] C[White lives.] )(;B[ap] ;W[ao] ;B[dr] ;W[ar] C[White lives.] ))(;B[ao] ;W[ap] C[White lives.] ))(;B[ap] ;W[cq] ;B[ao] ;W[aq] C[White lives.] )(;B[bq] ;W[cq] C[White lives.] )(;B[cq] ;W[bq] C[White lives.] )(;B[aq] ;W[cq] C[White lives.] ))(;W[cr] ;B[cs] ;W[bs] ;B[ap] ;W[ao] ;B[bq] ;W[cq] ;B[ar] C[RIGHT] )(;W[cq] ;B[bs] C[RIGHT] )(;W[bq] ;B[bs] C[RIGHT] )(;W[bs] ;B[ap] ;W[ao] ;B[bq] ;W[cq] ;B[ar] C[RIGHT] )(;W[aq] ;B[bs] C[RIGHT] ))(;B[cq] ;W[bq] C[White lives.] )(;B[bq] ;W[cq] C[White lives.] )(;B[cr] ;W[cq] (;B[bs] ;W[dr] ;B[ds] ;W[cs] C[ko.] )(;B[cs] ;W[bs] C[White lives.] )(;B[dr] ;W[bs] C[White lives.] )(;B[ap] ;W[cs] C[White lives.] )(;B[ar] ;W[dr] C[White lives.] )(;B[ds] ;W[bs] C[White lives.] ))(;B[dr] ;W[aq] (;B[bs] ;W[cs] ;B[cr] ;W[as] ;B[bq] ;W[cq] ;B[ds] ;W[bp] ;B[bs] ;W[ao] C[ko.] )(;B[bq] ;W[cq] ;B[bs] ;W[cs] ;B[cr] ;W[bp] ;B[ds] ;W[ao] ;B[ar] ;W[as] C[ko.] ))(;B[cs] ;W[bs] C[White lives.] )(;B[bs] ;W[cr] C[White lives.] )(;B[ar] ;W[cq] C[White lives.] )(;B[aq] ;W[cr] C[White lives.] )(;B[ap] ;W[cq] (;B[ao] ;W[aq] C[White lives.] )(;B[cr] ;W[cs] (;B[dr] ;W[aq] C[White lives.] )(;B[ao] ;W[aq] C[White lives.] ))))