(;
AB[bn][bo][en][fn][gn][do][dp][dq][dr][go][ho][io][jo][gp][jp][hq][hr]
AW[bl][bm][dl][dm][dn][fl][hm][jm][jn][eo][fo][ko][kp][fp][hp][ip][eq][gq][gr][iq][jq][lq]
C[Black plays.]
(;
B[gs]
C[The hane doesn't work.];
W[fs]
C[After White blocks, Black doesn't have a follow-up.];
B[fr]
C[For example ...];
W[hs]
C[... White connects all the stones.]
)
    (;
    B[fs]
    C[A stylish edge tesuji that often works to rescues stones, like the 2 marked.  But ...]
    TR[hq][hr];
    W[hs]
    C[... White can atari the 2 stones immediately.  Now Black cannot generate a liberty shortage for White's stones.];
    B[fq];W[fr];B[ep];W[fq]
    C[Black has nothing.]
    )
    (;
    B[hs]
    C[Another common connection tesuji, but this one works here.]
    (;
    W[ir];B[fs]
    C[Black takes this 2nd key point to create White's liberty shortage.]
    (;
    W[gs]
    C[For example ...];
    B[fq];W[fr];B[ep];W[is]
    C[White captures, but ...];
    B[fq]
    C[... Black rescues the 9 center stones.]
    )
        (;
        W[is]
        C[No better.];
        B[gs]
        C[White still has the liberty shortage.];
        W[es];B[fr]
        )
    )
        (;
        W[fr]
        C[Trying to extend liberties on this side doesn't work either.];
        B[ep];W[fq];B[fs];W[es];B[er]
        )
    )
)

