(;CA[ks_c_5601-1987]AB[pp][kp][pd][jd]AW[dd][cp][eq][iq]C[Lecture 8 Be careful before you attach Made by lovelove @L19 http\://www.lifein19x19.com/forum/viewtopic.php?f=15&t=7273] AP[MultiGo:4.4.4]SZ[19]AB[pj]MULTIGOGM[0] ;W[nq]LB[oq:A][pn:B]C[Attachment at A is usually a good move when there is a helping stone around K4. However, white J3 stone makes the difference. Black should extend at B here.] (;B[oq];W[np];B[pn];W[kq]C[White can easily link by attaching here.] (;B[lq];W[lp];B[jq];W[kr];B[jp];W[jr];B[lo];W[mp]C[White's territory is big.]) (;B[jp];W[jq];B[lp];W[nr]C[This move has two meanings\: Linking O3-L3 group and aiming lower right corner invasion.])) (;B[pn]LB[pr:A][kr:B][kq:C][qq:D]C[White should not play on A. If white wants to link, B is the only move. C does not work. D is the recommended move.] (;W[pr];B[qq]C[There is no space left for extension from O3.];W[no];B[mp];W[np] ;B[mq]C[O4 group will suffer or maybe die.]) (;W[kr]) (;W[kq];B[lq];W[lp];B[mp];W[lo];B[kr];W[jq];B[mq];W[ko];B[np]) (;W[qq];B[pq];W[pr] (;B[or];W[qr];B[oq];W[ro];B[rn];W[qo];B[qn];W[po];B[oo];W[qp];B[np]C[joseki]) (;B[qp];W[rr];B[rq];W[qr]C[joseki]))))