题目内容：

英语need should must have to
need
should
must
have to
它们各自的意思,用法,区别.

优质解答

should,must,need,都是情态动词,后面都只能跟动词原形,分别解释为应该,必须,需要.其中need可分为两类：一、need do,否定形式为needn't do,肯定回答为Yes,I need.否定回答为No,I needn't.二、need to do,否定形式为d...