本文主要對先秦助動詞“可”的句法、語義演變過程進行探討。“可”后動詞表被動、動詞不帶賓語的原因，在于當“可”由形容詞語法化爲助動詞時，“VO，可”中的V移到“可”之后。“可以”后動詞可以帶賓語的原因，在于介詞“以”的賓語位于主語位置上。“可以”后動詞表主動的原因，在于“可以”的“以”用作“作爲”義介詞。助動詞“可”主要表示“値得”、“條件可能”和“許可”三種語義。這三種語義的演變路徑是“値得→條件可能→許可”，其中“値得”義乃由形容詞“可”的“尙好”義演變而來。

This paper discusses the syntactic and semantic development of auxiliary verb ‘ke(可)’ in pre-Qin Chinese. The reason that the verb behind ‘ke(可)’ has passive meaning and does not take an object is because in the process of grammaticalization of ‘ke(可)’ from being an adjective to being an auxliliary verb, the ‘V’ in the syntactic structure of ‘VO, ke(可)’ has moved its position to the back of ‘ke(可)’. The reason that the verb behind ‘keyi(可以)’ can take an object is because the object of the preposition ‘yi(以)’ is located right in the subject position. The reason that the verb behind ‘keyi(可以)’ has active meaning is because the preposition ‘yi(以)’ of ‘keyi(可以)’ is used as an ‘as’ meaning. The auxiliary verb ‘ke(可)’ has three central meanings: ‘worth’, ‘root possibility’ and ‘permission’. Considering semantic relations between these three meanings, the path of semantic change could be ‘worth→root possibility→ permission’. The meaning ‘worth’ would be derived from ‘fine, okay’, which is the meaning of adjective ‘ke(可)’.