(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]RU[Japanese]SZ[19]KM[0.00]PW[White]PB[black];B[pd];AW[cc][fc][nc][qc]AB[dd][df][pf][ci][qj]LB[cc:B][qc:A]C[Situation 1 : What's the difference between A and B invasion ?];W[jp];B[dc];W[db](;B[eb];W[cb];B[ec];W[be];AE[cb][db][eb][cc][dc][ec][fc][nc][qc][dd][pd][be][df][pf][ci][qj][jp];AW[dd][dp]AB[qk][pq]C[Situation 2](;W[mq]C[old chinese fuseki];B[po];W[jq];B[fc];W[cf](;B[jd]C[no one plays like this anymore because of san-san invasion];W[qc]C[white takes a lot of territory];B[qd];W[pc];B[oc];W[ob];B[nc];W[nb];B[mc];W[rd];B[re];W[rc];B[qf];W[nm]C[how much can black make ?];B[nk];W[ll];B[lj];W[jk];B[ji];W[hj]C[not efficient moves this way for black];AE[nb][ob][fc][mc][nc][oc][pc][qc][rc][dd][jd][qd][rd][re][cf][qf][ji][hj][lj][jk][nk][qk][ll][nm][po][dp][jq][mq][pq];AB[nc][qd][qp][oq]C[Situation 3 : difference between two shimaris];W[qi];B[qk];W[qf](;B[qe];W[pf];B[oe](;W[of];B[ne]C[black is making a big corner];AE[nc][qd][ne][oe][qe][of][pf][qf][qi][qk][qp][oq];AW[dp]AB[pd][pp]C[Situation 4];W[dc];B[de];W[ce];B[cf];W[cd]C[what is black move ? (new joseki)];B[fq];W[cn];B[dg];W[fc];B[ck];AE[dc][fc][cd][pd][ce][de][cf][dg][ck][cn][dp][pp][fq];AW[dc][cd][ce][pp]AB[pd][de][cf][dg][dp]C[Situation 5];W[fc](;B[ck]LB[ch:A][cq:B]C[not efficient move : white has A and the corner at B is still open];AE[dc][fc][cd][pd][ce][de][cf][dg][ck][dp][pp];AW[dd][dq]AB[pd][co][pq]C[Situation 6];W[po];B[qm];W[qq];B[qp];W[pp];B[qo];W[qn];B[pn];W[rn];B[rq];W[qr];B[ro];W[oq];B[rm];W[on];B[pm]C[the right side is becomong big];W[qf]C[white tries to invade](;B[qe]C[if black pincer, it would be overconcentrated];AE[dd][qe][qf][pm][qm][rm][on][pn][qn][rn][co][po][qo][ro][pp][qp][dq][oq][pq][qq][rq][qr]C[Situation 7];W[nc];B[lc];W[pc];B[qc];W[qd];B[rc];W[qe];B[pe];W[pf](;B[oe]C[empty triangle is the best move here ! during a fightin];AW[gq]AB[co][go][dq][jq]C[but there are differences between empty triangle];W[ip];B[jp](;W[io];B[iq];W[hp])(;W[ho];B[hn];W[io]C[better empty triangle then the previous one because white has an eye shape in this situation]))(;B[of];W[oe];B[od](;W[nd];B[ne];W[oc];B[oe];W[qf])(;W[ne];B[qf];W[pg];B[re];W[nd];B[rd];W[ng])))(;B[qh];W[nc];B[pf];W[pg](;B[qg];W[qc];B[qe];W[pc]C[black is overconcentrated])(;B[of];W[qg];B[qe]C[best way for black : push white on black thickness])))(;B[cm]LB[cn:A]C[seems more efficient (A is also possible)];W[dj]C[if white come here];B[gf]C[black extend and white stone is not safe. So it's a possible sequence for black]))(;W[]C[if white does not push];B[of];W[og];B[ph]C[white became weak]))(;B[oe];W[rd];B[rc];W[re];B[qc]C[black seems overconcentrated])(;B[pd];W[re]C[black nobi is not that efficient];B[rd];W[sd];B[sc];W[se]))(;B[nc];W[re]))(;W[nc](;B[pf])(;B[nd];W[md];B[ne];W[oc];B[pc](;W[kc]C[better defense for white](;B[];W[od];B[oe];W[pe](;B[pf];W[qe];B[qf];W[rd];B[rf];W[pb]C[black corner is dead])(;B[qe];W[pf];B[qf];W[pg]C[good for white]))(;B[pf]C[black has sente to play keep is territory but it's slow...];AE[kc][oc][pc][md][nd][ne]C[If we change the order of moves];W[kc];B[nd];W[md];B[ne];W[oc];B[pc]C[too slox for black])(;B[mc]))(;W[jc];B[mc]C[what about the cut ?](;W[lc];B[mb];W[lb];B[me];W[ld]C[do not expect white to play this way, because white stone is too close to his wall])(;W[mb];B[lc];W[lb]C[The cut is not good enough. Black should play something bigger like approach the left bottom corner]))(;W[lc]C[tigger mouth not good];B[mb];W[lb];B[me]))(;B[oc](;W[nd];B[pf];W[jd]LB[nd:A]C[when we play chinese fuseki, we don't want white to have A high stone to destroy our own territory])(;AE[nc][oc][dd][qk][dp][pq]AW[de][cf][dg]AB[dc][fc][cd][ce]C[in this situation];W[nc]C[if black pincer, white would take the corner and black territory is smaller];B[oc]C[push our opponent to our thickness];W[nd];B[pf];W[jc];B[nb];W[mb];B[ob];W[lc]C[black gets a very big corner and white has to end gote because black is strong both sides]))(;B[kc]C[why this move doesn't work ? If black wants to pincer, he should play a space near to white stone];W[qc](;B[pc];W[qd];B[pe];W[pb];B[ob];W[qb];B[oc];W[qf]LB[qh:B][qo:A]TR[qk]C[marked stone would have been better at A or B])(;B[qd];W[pc];B[od](;W[mb]C[better choice in this situation])(;W[nd];B[oc];W[ob];B[pb];W[qb];B[nb];W[pa];B[mb];W[ne];B[rd];W[rc];B[pg]C[white is on trouble])(;W[mc];B[oc];W[ob];B[nb];W[pb];B[md];W[nd];B[ne];W[ld];B[mb]C[white is separated])))))(;B[cd];W[bb];B[bc];W[cb]))