情态动词had better,should,ought to用法点击
一、情态动词 had better
1. had better 表示“最好”,其缩写为“’d better”,表示“有义务做某事”。例如: He warned me that I had better not say anything about it.他警告我对此事最好只字不提。
The matter had better be left as it is.这事最好任其自然。
2. had better 表示提出建议、劝告或命令等,含有“应该做某事”之意,一般适用于对晚辈、平辈。例如:
I thought you had better have my opinion first.我想你最好先听听我的意见。
It’s very cold outside. You’d better put on more clothes.外面很冷,你做好多穿些衣服。
3. had better 否定形式为had better not,疑问句中had better 的否定形式有两种:Hadn’t + 主语 +better + 动词原
形;Had + 主语 + better not +动词原形。例如:
Hadn’t you better go with them? 你跟他们去不是更好吗?
Had we better not go? 我们不去不是更好吗?
4. Had better do sth. 有时可省略为 better do sth. 例如:
Better stay at home and have a good rest. 最好呆在家中好好休息。
二、情态动词 should, ought to
1. Should 作情态动词,表示劝告、建议,多指主观上有责任、有义务做某事,作“应该”解,语气比 ought to要弱。例如:
You should keep your promise.你应该履行诺言。
You should study first aid with the teacher.你应该跟老师学习急救法。
2. Ought to 表示客观上有责任、有义务做某事或非常可能的事,语气较强。其否定形式为 ought not to。例如:
You ought to drink plenty of water.你应该大量喝水。
You ought not to put any oil on the skin if it is burned. 如果皮肤烧伤,你不应该往上搽油。
3. Should , ought to 用于疑问句时, should 直接放在主语前,而ought 变疑问句时则把 ought 放在主语前,to放在主语后的动词前。例如:
Should I open the window? 我应该打开窗户吗?
——Ought he to go?他应该去吗? ——Yes, I think he ought to. 是的,我想他应该。
4. Should 与 ought to 还可以表示推测,表示说话者根据某种情况做出的肯定推测,其意义为“应该”。例如:
The wind has stopped blowing; it should be warmer. 风停了,天气该暖和了。
If she took the 9:30 a.m. train, she ought to be arriving now. 假如她搭上
早9:30 的火车,现在应该快到了。
5. Should 还可以用于动词 suggest, insist, order, demand 等宾语从句的虚拟语气中。例如:
I suggest that he apply for the job.我建议他申请这份工作。
She insisted that Tom should not take part in the meeting.她坚持要求汤姆不应该来参加会议。
6. “should / ought to + have + 过去分词”则表示本应该做某事而实际上未做,含有“责备”的意味。例如:
You should have come here five minutes earlier. 你本应该早五分钟到这儿。
You ought to have helped him. 你本应该帮助他。