  Inspired by the recent T2K indication of a relatively large theta_{13}, we
provide a systematic study of some general modifications to three mostly
discussed neutrino mixing patterns, i.e., tri-bimaximal, bimaximal and
democratic mixing matrices. The correlation between theta_{13} and two large
mixing angles are provided according to each modifications. The
phenomenological predictions of theta_{12} and theta_{23} are also discussed.
After the exclusion of several minimal modifications, we still have reasonable
predictions of three mixing angles in 3 Sigma level for other scenarios.
