Question

在什么情况下用be动词 和does do did

最好是给一个例句 ,然后解释 一下,谢谢了

Answer 1

如果你要跟的是一个实义动词，那就要用does, do, did,比如，I did not finish my homework, (不用翻译吧。。。)，再比如，Do you like watching TV?
finish like 都是有实际意义的动词。
如果你要跟的是一个形容词，副词，那就用系动词。比如，i am happy now. happy 就是一个形容词。i am here. here 就是一个副词。
你这么问应该学英语不久吧。慢慢来，看得多了就好了。

Answer 2

1.be 动词分为一般式am,is,are，过去式was,were等，其后加上形容词，名词等作表语，构成“主系表”结构，如：I am tall. He is a teacher.等
be+现在分词，构成进行时，如：They are running on the playground.
I was watching TV this time yesterday.
be+过去分词，构成被动语态，如：He was praised by the teacher.
They were invited to the party.
2.does, do, did 本身有实际意义“做”,如：He does homework everyday. I do homework everyday. We did our homework yesterday.
帮助主要动词构成疑问句和否定句，如：Did he come yesterday? I don't know.