(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]RU[Japanese]SZ[19]KM[7.50]GN[Save or sacrifice]PW[A]PB[B]DT[2013-01-18]PC[The KGS Go Server at http://www.gokgs.com/]RE[W+Resign]BC[cn]WC[kr](;B[pd]C[Yamada Takuji vs O Rissei (W)];W[dd];B[pq];W[cp];B[eq];W[qo];B[qk];W[lq];B[iq];W[op];B[oq];W[nq];B[np];W[oo];B[qp];W[mo]LB[ro:B][mq:A](;B[mq];W[nr]C[if white leaves black a ponuki, black has too much points and white is not safe against a cut];B[mp];W[lp];B[mr];W[lr];B[or];W[no];B[ns];W[kn]TR[pg][gq]C[this move aims for marked intersections. This is bad for black])(;B[ro]C[it's better for black to sacrifice his stone];W[nr];B[nn];W[no]))(;B[pd]C[Choi Jeong vs Wang Chenxing.];W[dd];B[qp];W[dp];B[fq];W[cn];B[lq];W[qj];B[qg];W[qm];B[pn];W[ro];B[pm];W[rp];B[ql];W[qq];B[pq];W[pp];B[op];W[qo];B[oq]LB[jc:A][oj:B]C[White to play.](;W[jc]C[best choice for white to sacrifice his stone](;B[fo];W[eq];B[fr];W[kn];B[cf];W[fd];B[cl];W[di];B[el])(;B[oj]C[white can later have sabaki's to live inside];W[qh];B[pg];W[rl];B[rm];W[rk]))(;W[oj];B[mj];W[nk];B[ll]C[white can escape but black thickness will be efficient and invasion would be impossible]))(;B[pd]C[Yang Dinxin vs Fang Tingyu];W[dd];B[qp];W[dq];B[oq];W[qf];B[nc];W[rd];B[fc];W[df];B[qh];W[qc];B[qe];W[re];B[pf];W[pg];B[qg];W[rf];B[og];W[gd];B[pj];W[dk];B[jp];W[no];B[mp];W[qo];B[po];W[pn];B[pp];W[pk];B[oj];W[nl];B[qn];W[pm];B[dc];W[cc];B[cb];W[ec];B[db];W[eb];B[ed];W[fb];B[cd];W[de];B[bd];W[be];B[gp];W[fp];B[fo](;W[dn]C[is it a good plan for white to leave his stone ?];B[ep];W[dp];B[fq]C[white is sente but right side is not alive yet and black has a powerful ponuki. Not a good idea for white to give up his stone];W[mo];B[dm]C[later black can invade here];W[cm];B[cn](;W[co];B[cl];W[bn];B[dl]C[white is separated])(;W[em];B[do];W[dl];B[cp]C[white corner is lost]))(;W[ep];B[go];W[dn]C[white is gote but black is less strong and left side is nearly safe]))(;B[pd];W[dc];B[dq];W[pp];B[ce];W[di];B[ed];W[ec];B[fd];W[gc];B[cc];W[gd];B[dd];W[gf];B[fc];W[fb];B[cb]LB[eb:A][nc:B]C[Morita (W) vs Cho Sonjin : where should white play ?];W[nc];B[qf];W[co];B[eb]TR[gb]C[black is gote. And even playing at the marked space, black will end gote. Futhermore, if white defends at the marked space, it would be slow])(;B[pd]C[O Meien vs Rin Shien];W[dd];B[qp];W[dq];B[do];W[co];B[cn];W[cp];B[cf];W[fc];B[dn];W[fq];B[dj];W[oq];B[po];W[qj];B[qh];W[qm];B[np];W[mq];B[lp];W[mp];B[mo];W[nq];B[lq];W[qr];B[rr];W[no];B[op];W[pq];B[qq];W[nn];B[qn];W[ro];B[pp];W[lo];B[mn];W[ko];B[mm];W[lr];B[pm];W[pl];B[nm];W[oi];B[pf];W[rm];B[jd];W[bd];B[ef];W[pc];B[oc];W[ob];B[od];W[pb];B[nb];W[qd];B[qe];W[rd];B[pj];W[pi];B[qi]LB[oj:A][ok:B]C[what is the best way for white ?](;W[oj];B[pk];W[ok];B[qk];W[rk];B[rj];W[ql];B[qj];W[ol];B[gp];W[fp]TR[lp][lq]C[what is the way to save black two stones ?](;B[kq]C[but is it good for black to save his stones ?](;W[kr];B[jp]C[black would hae a heavy group but if black would have nobi, white keima is strong to kill black stones];W[jq];B[kp];W[ip];B[jo];W[io];B[jn];W[in];B[im];W[jm];B[kn];W[hm];B[il];W[gn]C[black got strong shape to attack now];B[mi]C[at the end, black gets a Ko and kill top right corner])(;W[jq];B[kr];W[jr];B[mr]C[black got too much territory now]))(;B[go]C[if black plays too soft];W[jq]C[black does not have enough points and he is not to thick to attack white right group]))(;W[ok](;B[qk];W[rj](;B[pk];W[rk]C[black is dead])(;B[rk];W[pk];B[sj];W[oj];B[ri]))(;B[rj];W[qk];B[nj];W[oj];B[rk]C[white shape is destroyed and he his very heavy])))(;B[pd]C[Niu Yutian vs Liu Xing (b).];W[dd];B[pq];W[dp];B[fq];W[cn];B[qk];W[jq];B[dr];W[cq];B[lp];W[gp];B[gq];W[hp];B[eo];W[hq];B[ep];W[dq];B[cr];W[eq];B[er];W[fp];B[bq];W[bp];B[br];W[dm]LB[ch:A][em:B]C[Black to play (escape his two stones or sacrifice ?];B[ch]LB[hr:A][lr:B]C[white is alive everywhere so there is no point on saving those stones. A is sente for white and B makes him alive];W[cf];B[dk];W[hr];B[gs];W[di]TR[fm]C[white can choose to take black two stones but it is too small])(;B[qd]C[Park Chihoon(b) vs Cho Hunhyun];W[dd];B[qp];W[oc];B[cp];W[oq];B[kq];W[on];B[qm];W[hp];B[fq];W[fo];B[ep];W[ko];B[gp];W[go];B[hq];W[ip];B[iq];W[dn];B[cf];W[dh];B[cc];W[cd];B[dc];W[ed];B[bd];W[be];B[bc];W[ce];B[fc];W[pe];B[qe];W[pf];B[qg];W[pl];B[ql];W[pg];B[qf];W[hc];B[ph];W[oh];B[fd];W[fe];B[ge];W[gd];B[gb];W[ff];B[he];W[jc];B[ih];W[if];B[ie];W[jf];B[hg];W[kd];B[fg];W[df];B[ic]C[White to play](;W[ec]C[best way for white];B[eb];W[gc];B[fb];W[ib];B[ke];W[je];B[id];W[hb])(;W[ib];B[hd]C[white moyo is destroyed]))(;B[pd]C[Hashimoto Utaro vs Ishii Kunio];W[cq];B[qp];W[dc];B[oq];W[ce];B[qj];W[nc];B[kd];W[ne];B[pf];W[qc]C[white could have played the keima joseki but it's too good for white];B[pc];W[pb];B[ob];W[qb];B[oc];W[re];B[md];W[nd];B[mb]LB[ng:A][jp:B]C[White to play](;W[jp]LB[lb:B][mc:A]C[black is connected (exchange A to B) so there's no point on saving his three stones])(;W[ng]C[white can save his stones but black would get something big];B[ni];W[mh];B[lj];W[kh];B[jj];W[ih];B[hj];W[gh];B[ip]))(;B[pd]C[Chen Yaoye(b) vs Kang Dongyun];W[dp];B[qp];W[dc];B[oq];W[qf];B[nc];W[rd];B[qg];W[pg];B[qh];W[ph];B[rf];W[qe];B[qj];W[pi];B[qk];W[qc];B[kc];W[ce];B[cn];W[fq];B[bp];W[cq];B[ck];W[kq];B[of];W[pc];B[oc];W[oe];B[ne];W[gc];B[en];W[hp];B[pf];W[pe];B[nf];W[ok];B[od];W[re];B[ni]LB[oj:B][mk:A]C[White to play](;W[mk]C[right shape because black can't achieve something attacking from left or bottom this two stones];B[rg];W[rb];B[nl];W[nk];B[pm])(;W[oj];B[mk];W[nl];B[hd]C[black has a big potential]))(;B[pd]C[Yoda Norimoto (b) vs Ri Ishu];W[dd];B[qp];W[dq];B[oq];W[qj];B[qh];W[qm];B[pl];W[qo];B[ql];W[rl];B[rk];W[rn];B[sl];W[rm];B[qk];W[qq];B[pp];W[rp];B[qr];W[rr];B[pq];W[rq];B[on];W[do];B[iq];W[qc];B[qd];W[pc];B[nc];W[nb];B[mb];W[oc];B[nd];W[od];B[oe];W[rd];B[re];W[ne];B[of];W[ob];B[lc];W[me];B[ld];W[rc];B[fc];W[le];B[ke];W[kf];B[jf];W[je];B[kd];W[jg]LB[if:A][lf:B](;B[if];W[lg];B[kh];W[kg];B[ie])(;B[lf];W[if];B[lg]TR[ic][cg]C[white ponuki is strong to build something big at the left side or the top can be dangerous for black]))(;B[pd]C[Hikosaka vs Nakamura Hidehito];W[dc];B[pq];W[eq];B[cp];W[qo];B[pm];W[oo];B[np];W[lp];B[no];W[on];B[mn];W[qq];B[qr];W[rq];B[pp];W[qn];B[hp];W[do];B[co];W[dn];B[cm];W[ln];B[mm];W[lm];B[ml];W[hn];B[qm];W[rr];B[jp];W[io];B[lq];W[ip];B[iq];W[hq];B[jq];W[ck];B[dm];W[hr];B[dq];W[er];B[qf];W[jc];B[de];W[cg];B[cc];W[cb];B[cd];W[eb];B[ef];W[di];B[id];W[gd];B[cf];W[dg];B[ic];W[gf];B[dd];W[fc];B[be];W[jd];B[je];W[ke];B[kd];W[kb]LB[ld:B][ie:A]C[Black to play ](;B[ld];W[jf];B[ie];W[ib]LB[lb:A][if:B](;B[lb]C[black should sacrifice his four stones to build a moyo];W[if];B[mf];W[kf];B[hb]C[black plays this move to gain more points on yose];W[hc];B[rn];W[ro];B[rm];W[pr];B[or];W[qs];B[mi]C[black gets everything on the right side so he won the game];W[qc]C[If white tries to invade, can he live ?](;B[pc]C[too soft];W[qd];B[qe];W[pb];B[ob];W[rb];B[pa];W[qa]C[Usually it's a Ko fight])(;B[pb]C[it's possible but black shape is not solid];W[pc];B[ob])(;B[ob]C[keima is the common move when black is strong outside];W[pb];B[rd];W[oc];B[nb]))(;B[if];W[le];B[md];W[jg]C[now black is too heavy to live and gain something on the right]))(;B[ie];W[ld]C[black is heavy and white is very stong . So black can't build a big territory on the right because he his going to attack black stones];B[kf];W[le];B[jg];W[lf]))(;B[qd]C[Park Chunsang vs Lee Youngkyu];W[pp];B[cd];W[dp];B[qn];W[ql];B[oc];W[ed];B[ec];W[fc];B[dc];W[gd];B[cf];W[kc];B[qq];W[qp];B[pq];W[op];B[rp];W[ro];B[rq];W[qo];B[nq];W[qi];B[fq];W[eq];B[fp];W[dn];B[ip];W[mo];B[cq];W[fr];B[gr];W[er];B[co];W[do];B[bn];W[bm];B[jd];W[jc];B[cm];W[cn];B[bo];W[bl];B[br];W[hq];B[dl];W[dk];B[ek];W[dj];B[gq];W[fn];B[cl]LB[ck:A][el:B][fl:C]C[black mistake, how can white punish ? (black shoud have played C];W[el]C[A is a difficult fight for white];B[ck](;W[ej]C[very good move](;B[bk];W[fk]C[very good for white to get this ponuki !])(;B[fk]C[if black escape ...];W[bk];B[cj];W[ci];B[em];W[fl];B[fm];W[gl];B[dm];W[gm];B[bj];W[bi]))(;W[cj];B[fl];W[em];B[bk];W[bj];B[am]C[white is separated]))(;B[qd]C[Kobayashi Izumi vs Mannami Kana];W[pp];B[dc];W[cp];B[ce];W[nc];B[lc];W[qc];B[pc];W[pd];B[qb];W[rc];B[od];W[pe];B[oc];W[rb];B[ep];W[eq];B[dp];W[dq];B[co];W[cq];B[fp];W[gq];B[dn];W[pf];B[nd];W[di];B[bp];W[cl];B[bq];W[fq];B[cm];W[dl];B[ch];W[dh];B[ci];W[cj];B[dg];W[eg];B[df];W[fh];B[bj];W[qn];B[dj]LB[ej:B][ck:A]C[White to play.];W[ej]C[if white plays A, black nobi has separated white stones];B[ck];W[dk]C[black has no ko threats];B[cj];W[fk])(;B[qd];W[pp];B[cd];W[dp];B[qn];W[nq];B[pj];W[nc];B[pc];W[kc];B[ic];W[me];B[ie];W[pe];B[qe];W[pf];B[qf];W[ph];B[cn];W[cl];B[cq];W[cp];B[dq];W[ep];B[bp];W[bo];B[bq];W[co];B[fq];W[ed];B[ec];W[fc];B[dc];W[gd];B[gf];W[ff];B[gg];W[df];B[bf];W[ge];B[jg];W[hf];B[he]LB[fg:A][hg:B](;W[hg]C[if black nobi, white can nobi or kosumi and black would still have two groups];B[hh];W[gh];B[fg];W[ih]C[white can fight because he his thick on both side])(;W[fg];B[gh]TR[pe][pf][ph][cl][bo][co]C[if white plays like this, his thickness would be difficult to use]))(;B[pd]C[Cho Hanseung vs Mok Jinseok];W[dp];B[qp];W[dc];B[fq];W[cn];B[kq];W[qj];B[pk];W[qk];B[pl];W[ql];B[qm];W[pj];B[qg];W[qq];B[pq];W[qn];B[pm];W[rm];B[pn];W[qo];B[rp];W[po];B[oo];W[pp];B[op];W[ro];B[rq];W[qr];B[so];W[rn];B[rr];W[oq];B[pr];W[or];B[qs];W[lp];B[kp];W[lo];B[ko];W[ln];B[nk];W[kn];B[oj];W[ph];B[qh];W[oi];B[ni];W[nh];B[mi];W[in];B[hp];W[nc];B[pb];W[pg];B[qf];W[mh];B[li];W[jc]LB[de:A][nq:B]C[Black to play];B[de]C[black does not need to take two white stones because he is strong on the center. ANd this kakari is much bigger than 10 points at the bottom])(;B[qd]C[Ma Xiaochun(Black) vs Zhang Wendong];W[dd];B[pq];W[oc];B[cp];W[po];B[ld];W[qq];B[pc];W[qj];B[qr];W[qp];B[or];W[od];B[pe];W[nf]LB[mc:A][oe:B]C[Black to play];B[mc];W[oe];B[pf])(;B[pd]C[Kobayashi Koichi (b) vs Yamashiro];W[dp];B[pq];W[dd];B[qk];W[kq];B[fc];W[cf];B[ic];W[fp];B[pf];W[jd];B[jc];W[kd];B[he];W[kg];B[mq];W[dj];B[lo];W[ok];B[jp];W[iq]LB[lh:A][pi:B]C[Black to play](;B[lh]SQ[ok]C[if black can kill marked stone, is moyo would be very big];W[ng];B[oh];W[mi];B[lg])(;B[pi];W[oi];B[ph];W[li]TR[qc][ql][qq]C[white groups are connected and can reduce black playing at the marked space]))(;B[pd]C[Ma Xiaochun (b) vs Wang Lei];W[dd];B[qp];W[dp];B[fq];W[hq];B[oq];W[cn];B[fc];W[cf];B[db];W[cc];B[ic];W[qf];B[qh];W[qc];B[qd];W[pc];B[od];W[rd];B[re];W[rc];B[rf];W[nc];B[jq];W[dq]LB[fo:A][hp:B]C[Black to play];B[hp]LB[fd:D][hd:C]C[running with A will reduce black moyo on the right because white would have a wall and white can have C and D to block black];W[gp];B[ho];W[gq];B[go];W[fp];B[kn])(;B[];AW[dd][rd][of][qf][oj][qj][dp]AB[kc][nc][qc][pd][cj][ql][qp][oq];W[qn]C[if white invade , what sould black do ?];B[pn];W[pm](;B[qm];W[po];B[rn];W[on];B[qo]C[black territory is safe and he has points (but it's not so big)];W[ro]C[later, white can play this];B[rm];W[qq])(;B[on]C[best move for black (nobi the other side is also possible)];W[qm];B[om];W[pl]C[black has a powerful shape in sente])))