①too…to… "太……而不能……"。
如:The boy is too young to look after himself. 那个男孩太小而不能照顾自己。
②…enough to…"……足够……"。
如:He is old enough to go to school. 他足够大能去上学了。
③Why don’t you +省略to的不定式?=Why not +省略to的不定式?为什么不……呢?
如:Why don't you get her a photo album? =Why not get her a photo album? 为什么不给她买个相册呢?
④had better+(not)+省略to的不定式。最好(不要)做……
如:You'd better not stay here today. 你今天最好别待在这儿。
⑤Will you please+省略to的不定式?你愿意……吗?
如:Will you please close the door? 能请你把门关上吗?
⑥prefer to do sth. rather than do sth. "宁愿做某事而不愿做某事"
如:I prefer to do more work rather than do nothing at home.我宁愿做更多的工作也不愿在家无所事事。
⑦It is+adj.+for/of sb.+to do."做某事是……的"
如:It is necessary for us to brush our teeth twice a day.一天刷两次牙对我们是有必要的。
It’s hard to say which one is better.很难说哪一个更好。
It was great fun to have a picnic there. 在那里野餐很有意思。
It took me 2 hours to finish my homework. 完成作业花了我两个小时的时间。