不可解特征与二语习得中的隐性主语

英语时态短语中心语T拥有语义不可解主格强特征,要求主语必须显性标注。汉语中充当主语的词条只需要具备[＋D/N]特征就能够满足T的EPP特征,所以主语在拼读时可以省略。习得者在习得英语句法节点特征或词条特征之前,会把其L1（如汉语）中的隐性标注特征以默认值的形式迁移到L2英语句法当中,导致L2英语句法中的隐性主语出现。

Uninterpretable Features and the Covert Subject in SLA

The head T in English,as claimed in the Minimalist Programme,carries strong and uninterpretable nominative features which require that the subject be overtly marked.The head T in Chinese,however,has the weak and uninterpretable nominative features,for which the subject can be overtly or covertly marked.And Chinese L2 English learners,accordingly transfer the superset features of Chinese into their L2 English syntax as the default form of pro-drop parameter,leading to the existence of L2 English null subjects.