Black to live
This is common shape, but it wasn't on the site, if there is a similar problem, let me know
(;SZ[19]AW[mp]AW[np]AW[op]AW[kq]AW[lq]AW[pq]AW[qq]AW[rq]AW[kr]AW[rr]AB[nq]AB[oq]AB[lr]AB[mr]AB[pr]AB[qr]C[Black to live]GM[1]FF[4]CA[UTF-8]AP[CGoban:2]ST[2]RU[Japanese]KM[6.50]
(;B[os];W[ls]TR[mq]C[This is the right side because of the triangle liberty]
(;B[nr]C[RIGHT])
(;B[qs]C[RIGHT])
(;B[ns];W[qs])
(;B[ms];W[nr];B[qs];W[mq]C[Oups]))
(;B[ns];W[or];B[os];W[qs]
(;B[ps];W[ls])
(;B[ls];W[ps])
(;B[nr];W[ls]))
(;B[nr];W[os]
(;B[ns];W[ls])
(;B[qs];W[ls]))
(;B[mq];W[qs];B[os];W[ls])
(;B[ls];W[qs]
(;B[ns];W[or])
(;B[os];W[ns];B[nr];W[rs]
(;B[ms];W[ps])
(;B[ps];W[or])))
(;B[qs])
(;B[or];W[ns]
(;B[qs];W[os])
(;B[os];W[qs])))