(;
AB[pb][pc][pd][pe][qb][qf][qg][rg]
AW[rb][qc][qd][qe][rf][sf]
C[Black plays.

Source:
Life and Death Problems from Actual Play
Nakaoka Jiro 7P
Go World #27, pp. 33-34,  Spring 1982]
(;
B[ra]
C[A big mistake.];
W[sb]
C[White instantly creates the "comb", a well-known living shape that every go player should instantly recognize.]
)
    (;
    B[sd]
    C[Black takes a vital point, but ...];
    W[rd]
    C[... White has this nice defensive resource.]
    (;
    B[sc];W[rc]
    (;
    B[sg];W[sb]
    C[White lives.]
    )
        (;
        B[ra]
        C[No better.];
        W[se]
        C[White makes eyes.]
        )
    )
        (;
        B[sb]
        C[This attachment also looks good, but ...];
        W[se];B[ra];W[rc]
        C[... again White catches Black's stones in a liberty shortage.]
        )
    )
    (;
    B[sb]
    C[This clamp is a move to remember.];
    W[ra];B[sd]
    (;
    W[rd];B[sg];W[re];B[rc]
    C[Black sets up a ko that White can take 1st.]
    )
        (;
        W[rc]
        C[A mistake.];
        B[re];W[rd];B[sg]
        C[After Black's snapback, White has only one eye.]
        )
    )
    (;
    B[rc]
    C[Note that Black can also set up a ko with this cut.

However, White has a couple possible responses, and the reader work out that the ko in the previous variation is better for Black.]
    )
)

