文档介绍：八年级上册第九单元英语课件
Can you come to my party?
Sure, I’ love to.
Sorry, I can’t .
I have to play soccer with my frien1. can 的用法
〔１〕表邀请。
　　假设承受邀请，答复为：
　　 OK./All right./Sure./ Of course./Certainly./
Yes(Sure),I’d love(like) to.
　　假设不承受邀请，答复为：
　　 Sorry,Ｉcan’t.(+原因)
Can you come to the party?
Yes/Sure,I’d love/like to.
Sorry, I can’t. I have to help my parents.
其他表邀请的句型:
1) Could /Will/Would you come to the party?
2) Would you like /love to come to the party?
3) I hope you come to the party.
4) Please come to the party.
5) How/What about coming to the party?
〔２〕表才能“能，会〞否认句 can’t不能
He can swim,but I can’t.
〔３〕在否认句，疑问句中表示“不可能〞或“一定不〞
Can he come ?No,he can’t come.
“have to〞与其他的情态动词如：“can〞 , “may〞 “must〞和 “should〞不同。
〔1〕这4个情态动词没有人称和数的变化,而have to有。它的第三人称单数为“has to〞，过去时为had to, 如：
He should study hard .
他应该好好学****br/> He has to study hard .
他不得不好好学****br/>〔2〕这4个情态动词在一般疑问句中将它们放在句首，在否认句中直接在他
们后边加not即可。
我们以can为例：
Can he go with us ?
他能和我们一起去吗？
He can’t go with us .
他不能和我们一起去。
而“have to〞要加助动词do ,
has to要加助动词does ，复原 have to
had to要加助动词did，复原 have to 才可能完成其疑问、否认句。
have to强调客观上需要做某事，即表示外界　　　条件的需要不得不做某事，含有“客观所迫〞的意味，它有人称和数的变化，可用于多种时态中，否认式为“不必〞。
　must强调说话者主观上认为必须做某事，含有“主观判断〞的意味，它的否认式意为“制止，不允许〞。
If one gets ill, he’ll have to see a doctor.
She has to go to school by bus.
We must go to school on time.
---Must I finish the homework now ?
---Yes, you must./No, you needn’t (don’t have to).
You mustn’t play football in the classroom.
I have to help my parents.
我不得不帮助我的父母。
help sb. with sb. (to) do sth.
上一句我们可以说：
I have to help my parents with the
housework .
或说I have to help my parents (to) do
the housework .
1. Jeff