1. 用作连系动词，其后可接名词、描述词、过来分词等作表语。如：He became a teacher at (the age of) 17. 他17岁就当了教师。The weather became warmer. 天气变得温暖起来。Soon the roombecame crowded. 不一会儿房里就挤满了人。留意：其后接过来分词时，可示意被动或后果；但示意被动时，其后普通不接 by短语。比方不说 Soon the room became crowded by students.
2. become 是终止性动词，因而要示意“成为…有多长工夫”有多长工夫，英语不能将become与示意一段工夫的词或短语连用。如：
他成为教师有十年了。正：He became a teacher ten years ago. 正：It’s ten years since he became a teacher. 正：He has been a teacher for ten years. 误：He has become a teacher for ten years. 3. become 之后普通不接不定式示意“逐步…” (此时可用 come, begin＋不定式)。如：＋不定式正：He began [came] to like English. 他开端喜爱英语起来。误：He became to like English. 正：He became ill yesterday. 他昨天病了。误：He became to be ill yesterday. 4. 用于习语 become of, 示意“发作”、“遭逢”等 (常与 what连用)。如：What has become of the girl? 这个女孩起初怎么了?
Idon’t know what will become of me if I fail this time. 要是我这次不胜利，我不知我会怎样样。