用法：

　　1.用作連系動詞，其后可接名詞、形容詞、過去分詞等作表語：

　　He became a teacher at (the age of)17.他17歲就當了老師。

　　The weather became warmer.天氣變得暖和起來。

　　注意：其后接過去分詞時，可表示被動或結(jié)果；但表示被動時，其后一般不接by短語。比如不說：

　　Soon the room became crowded bystudents.

　　2.become是終止性動詞，因此要表示“成為…有多長時間”，英語不能將become與表示一段時間的詞或短語連用：

　　他成為老師有十年了。

　　正：He became a teacher ten years ago.

　　正：It’s ten years since he became a teacher.

　　誤：He has become a teacher for ten years.

　　3.become之后一般不接不定式表示“逐漸…”(此時可用come/begin＋不定式)：

　　正：He began [came] to like English.他開始喜歡英語起來。

　　誤：He became to like English.

　　正：He became ill yesterday.他昨天病了。

　　誤：He became to be ill yesterday.

　　4.用于習語becomeof,表示“發(fā)生”、“遭遇”等(常與what連用)：

　　What has become of the girl?這個女孩后來怎樣了?

　　I don’t know what will become of me if I fail this time.要是我這次不成功，我不知我會怎么樣。