1、stop to do sth. 停下正在做的事去作另一件事
    stop doing sth. 停止正在作的事
    eg. When the teacher came into the classroom, the students stopped talking. After he worked for an hour, he stopped to have a rest.

2、forget / remember to do sth.忘记/记得要去作某事
    forget / remember doing sth. 忘记记得曾经做过某事
    eg. Please remember to bring my book to school.
I remember doing my homework

3、used to do sth. 过去常常作某事
    be used to do sth. 被用来作某事
    be used to doing sth. 习惯于作某事
    eg. My father used to smoke.
    Wood is used to make paper.
    I am used to getting up early.

4、So +be/助动词/情态动词 + 主语
　 …也一样
　 So +主语+be/助动词/ 情态动词
　 是呀,表示赞同别人的观点
　 Neither + be /助动词/ 情态动词+主语
　 …也不一样(用于否定句)
    eg. He has been to Beijing. So have I.
    It’s a fine day. So it is.
    She doesn’t like eggs. Neither do I.

5、too…to do sth. 太…而不能…
　 so +adj. /adv + that(从句) 如此…以致…
　 such +(a/an +adj.)+n.+ that(从句) 如此…以致…
　 (not) enough (for sb.) to do sth. (对某人来说)做某事(不)够
    eg. The boy is too young to go to school.
    The boy is so young that he can’t go to school.
    He is such a young boy that he can’t go to school.
    The boy is not old enough to go to school.