I.Critical Period Hypothesis and L2 Phonological Acquisition It seems to be commonly believed that children under certain age are better and quicker learners in a second language,especially in acquiring a native-like accent厂Critical period theory’(CPH) I. Period Period Hypothesis and L2 Phonological Acquisition It seems to be commonly believed that children under certain age are better and quicker learners in a second language, especially in acquired a native-like accent plant Critical period theory ’(CPH)