介词作为英语中最为活跃的词汇之一，一直是传统教学的难点。

Preposition is one of the most active parts of speech in English.

youdao

介词作为英语中最为活跃的词汇之一，一直是传统教学的难点。

Preposition is one of the most active parts of speech in English.

youdao