(;
AB[cl][bm][bn][em][fm][fo][fp][fq][aq][hq][cr][hs]
AW[cn][dn][ap][cp][dp][gp][bq][jq][er][ir]
C[Black plays.

Source:
    Gokyo Seimyo:  a classic endgame collection.];
B[eq];W[dr];B[dq];W[cq];B[br]
C[So far, straightforward.];
W[ar];B[bs]
C[An empty triangle, but the 1st tesuji.];
W[aq]
C[White can try to capture the 3 stones, but ...];
B[fr];W[as];B[cs]
C[... Black plays the 2nd tesuji.  White has only 1 gote eye in the corner.];
W[bo]
C[So White must create outside eye opportunities.];
B[es];W[ds];B[cr]
C[White lives, but the corner is very small.]
)

