主讲：朱明高级工程师、高级技师、国家经济师高级国家职业技能鉴定考评员高级技能专业教师综合英语2Unit8 语法知识点had better表示"最好"had better 相当于一个助动词，它只有一种形式，它后面要跟动词原形。

had better do sthhad better not do sthIt is pretty cold. You'd better put on my coat.She'd better not play with the dog.had better have done sth表示与事实相反的结果，意为"本来最好"。

You had better have come earlier.不定式作补语1) 动词+宾语+不定式(to do)advise，allow，appoint，believe，cause，challenge，command，compel，consider，declare，drive，enable，encourage，find，forbid，force，guess，hire，imagine，impel，induce，inform，instruct，invite，judge，know，like，order，permit，persuade，remind，report，request，require，select，send，state，suppose，tell，think，train，trust，understand，urge，warn例句：a.Father will not allow us to play on the street.父亲不让我们在街上玩耍。

b.We believe him to be guilty.我们相信他是有罪的。

Find 的特殊用法：Find 后可用分词做宾补，或先加形式宾语，再加形容词，最后加带to 的动词不定式。

find后也可带一个从句。

此类动词还有get，have。

I found him lying on the ground.I found it important to learn.I found that to learn English is important.典型例题:The next morning she found the man ___ in bed，dead.A. lyingB. lieC. layD. laying答案：A.find的宾语后面，用分词或分词短语，起宾语补足语作用。

现在分词表达主动，也表达正在进行，过去分词表达被动。

2) to + be 的不定式结构，作补语的动词。

Acknowledge, believe, consider, think, declare(声称),discover, fancy(设想),feel，find,guess, judge, imagine, know, prove, see(理解), show, suppose, take(以为), understandWe consider Tom to be one of the best students in our class.我们认为汤姆是班上最好的学生之一。

典型例题Charles Babbage is generally considered___ the first computer.A. to inventB. inventingC. to have inventedD. having invented答案：A. 由consider to do sth. 排除B、D。

此句只说明发明这一个事实，不定式后用原形即可。

而C为现在完成时，“发明”为点动词一般不用完成时，且此处也不强调对现在的影响，因此不选C。

3) to be +形容词Seem, appear, be said, be supposed, be believed, be thought, be known, be reported,hope, wish, desire, want,plan, expect, mean…The book is believed to be uninteresting.人们认为这本书没什么意思。

4)there be+不定式believe, expect, intend, like, love, mean, prefer, want, wish, understandWe didn't expect there to be so many people there.我们没料到会有那么多人在哪里。

注意：有些动词需用as 短语做补语，如regard, think believe, take, consider.We regard Tom as our best teacher.我们认为汤姆是我们最好的老师。

Mary took him as her father .玛丽把他当作自己的父亲2）表示在过去一段时间内，经常性或习惯性的动作。

When I was a child, I often played football in the street.Whenever the Browns went during their visit, they were given a warm welcome.3）句型：It is time for sb. to do sth"到……时间了""该……了"It is time sb. did sth. "时间已迟了""早该……了"It is time for you to go to bed.你该睡觉了。

It is time you went to bed.你早该睡觉了。

would (had) rather sb. did sth.表示'宁愿某人做某事'I'd rather you came tomorrow.4) wish, wonder, think, hope 等用过去时，作试探性的询问、请求、建议等。

I thought you might have some. 我以为你想要一些。

比较：一般过去时表示的动作或状态都已成为过去，现已不复存在。

Christine was an invalid all her life.(她已不在人间。

)Christine has been an invalid all her life.(她现在还活着)Mrs. Darby lived in Kentucky for seven years.(达比太太已不再住在肯塔基州。

)Mrs. Darby has lived in Kentucky for seven years.(现在还住在肯塔基州，有可能指刚离去)注意：用过去时表示现在，表示委婉语气。

1）动词want, hope, wonder, think, intend 等。

Did you want anything else?I wondered if you could help me.2）情态动词could, would.Could you lend me your bike?比较过去时与现在完成时1）过去时表示过去某时发生的动作或单纯叙述过去的事情，强调动作；现在完成时为过去发生的，强调过去的事情对现在的影响，强调的是影响。

2）过去时常与具体的时间状语连用，而现在完成时通常与模糊的时间状语连用，或无时间状语。

一般过去时的时间状语:yesterday, last week，…ago, in1980, in October, just now, 具体的时间状语共同的时间状语:this morning, tonight, this April, now, once，before, already, recently，lately现在完成时的时间状语：for, since, so far, ever, never, just, yet, till / until, up to now, in past years, always,不确定的时间状语3）现在完成时可表示持续到现在的动作或状态，动词一般是延续性的，如live, teach, learn, work, study, know.过去时常用的非持续性动词有come, go, leave, start, die, finish, become, get married等。

举例：I saw this film yesterday.（强调看的动作发生过了。

）I have seen this film. （强调对现在的影响，电影的内容已经知道了。

）Why did you get up so early?（强调起床的动作已发生过了。

）Who hasn't handed in his paper?（强调有卷子，可能为不公平竞争。

）She has returned from Paris.她已从巴黎回来了。

She returned yesterday. 她是昨天回来了。

He has been in the League for three years.(在团内的状态可延续)He has been a League member for three years.(是团员的状态可持续)He joined the League three years ago.(三年前入团，joined为短暂行为。

)---Will somebody go and get Dr. White?---He's already been sent for.句子中如有过去时的时间副词（如yesterday, last, week, in 1960）时，不能使用现在完成时，要用过去时。

（错）Tom has written a letter to his parents last night.（对）Tom wrote a letter to his parents last night.疑问句：定义：表达疑问（亦即发问）或请求的句子叫做疑问句。

例：Is he a friend of your brother's? （他是你哥哥的朋友吗？——发问）Can you do this for me? （你能替我做这件事吗？——请求）疑问句的句末必须使用问号“”来标示问句的结束。

疑问句：可分为一般疑问句、特殊疑问句、选择疑问句、反意疑问句和否定疑问句。