学习英语的时候要注意语法和一些词的用法，下面小编就为大家整理一下助动词有哪些。
英语中常见的助动词包括：
1.行为动词类：do, does, did
1. 现在进行时态中的be动词：am, is , are ,
2. 过去进行时态中的be动词：was, were
3. 一般将来时态中的助动词：shall, will,
4. 现在完成时态助动词： have, has
5. 过去完成时态助动词：had
6. 情态动词类：can, may, must, should, could, would, might, have/has to, used to,
7. 被动语态助动词：be 的各种时态.
情态动词与助动词
1、can
能，可以，表说话人同意，许可还可表客观条件许可，如:You can go now.
提建议或请求时可用can I, can you表客气，如Can I buy you a drink?
2、may
(1)可以，表说话人同意，许可或请求对方许可。You may go.
(2)(现在和将来)可能，也许，只用于肯定句和否定句中，如He may not be right.
3、must, have to
must表主观上的必须，have to表客观上的必须，如: It's getting late. I have to go. -Must I go now. -Yes, you must. (No, you needn't./ No, you don't have to.)
4、need, dare这二词有实意动词和情态动词两种词性，如用作实意动词后接动词不定式to do，如用作情态动词后接动词原形。Need I go now? --Yes, you must./No, you needn't.)
5、shall用于第一人称疑问句中表说话人征求对方的意见或向对方请求，如，Shall we begin our lesson?
用于二、三人称陈述句，表说话人命令、警告、允诺、威胁等口吻，如: You shall fail if you don't work harder.
6、should表应该，意为有责任，有义务。如:We should try our best to make our country more beautiful.
7、will表有做某事的意志、意愿、安心、打算，如 "Will you lend me your book?" "Yes, I will."
8、should have done表应该做而未做
must have done表对过去事实的肯定推测
could have done表本可以做某事
9、判断句：肯定句用must, 否定句用can't, 不太肯定用may, might
He must be in the office now.
He must have gone to bed, for the light is out.
He can't be in the office. He is at home.
He couldn't have cleaned the classroom, because he didn't come here today.
He might be in the office, I am not sure.
He might have cleaned the room, I suppose.