助动词协助主要动词完成以下功用,可以用来：a.表示时态,例如：He is singing.他在唱歌.He has got married.他已结婚.b.表示语态,例如：He was sent to England.他被派往英国.c.构成疑问句,例如：Do you like college life?你喜欢大学生活吗?Did you study English before you came here?你来这儿之前学过英语吗?d.与否定副词not合用,构成否定句,例如：I don't like him.我不喜欢他.e.加强语气,例如：Do come to the party tomorrow evening.明天晚上一定来参加晚会.He did know that.他的确知道那件事.3） 最常用的助动词有：be,have,do,shall,will,should,would
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