高中英语主要有那些重要单词和语法?
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高中英语主要有那些重要单词和语法?
高中英语主要有那些重要单词和语法?
高中英语主要有那些重要单词和语法?
重点语法 构词法:
在英语中,词的构成方法主要有三种,即合成、转化和派生. 1.合成法
把两个或两个以上独立的词合成一个新词的方法叫合成法,也叫合词法. (1)合成名词 highway 公路 (2)合成形容词
hand-made 手工制作的 good-looking相貌好看的 dark-blue 深蓝 (3)合成动词
ill-treat 虐待 mass-produce 大规模生产 safe guard 保卫 (4)合成副词
however 然而 downstairs 在楼下
(5)合成代词 anybody nobody something 2.转化法
转化是指词由一种词类转化为另一种词类. (1)动词转化为名词
常用give, take, have, make等动词与其搭配构成动词词组,表示一个动作. eg: give a smile 微笑 give a tick 踢 take a seat 就座 take a bath 洗澡 have a swim 游泳 have a talk谈话 make a wish 许愿
(2)形容词转化为副词
How long is the road?那条路有多条?(形容词)
How long have you been working there?你在那里工作了多久?(副词) (3)形容词转化为动词 eg:
The storm slowed down to half its speed. 风暴速度减慢了一半. The girls gradually quieted down. 女孩子们慢慢安静了下来了. (4)名词转化为动词 eg:
The hall can seat two thousand people.大厅能坐2000人.
The passengers have booked their plane ticket.旅客们已经订了飞机票. (5)形容词转化为名词
Something has gone wrong with the tool.工具出了点毛病.(形容词) Little children didn’t know the difference between right and wrong. 小孩子不能辨别是非.(名词) 3.派生法
派生是由词根加词缀(前缀、后缀)构成新词.除少数前缀外,前缀一般只改变词的意义,不改变词性;后缀一般只改变词性,不引起词义的变化.
情态动词
情态动词表示说话人对某一动作或状态的态度,如可能、义务、必要、猜测等.但本身词义不完全,不能单独做谓语动词,必须和动词原形连用.情态动词没有人称和数的变化.每一个情态动词都有自己的具体含义,都有自己的使用特点.
1. can:能力、可以、会.表“许可”时可代替may,但may比较正式. eg: Most young men can use computers. 大部分年轻人会用计算机. 2. could: can的过去式,也可表示语气委婉. eg: Could you wait for a while?请你等一会儿好吗? 3. be able to:能力.比can有更多的形式,但表示过去成功地做了某事时只能用was/were able to,不能用could. eg:
He was able to reach Mount Qomolangma in 1982.他在1982年成功地登上珠穆朗玛峰. 4. may:许可、可能 eg:
You may borrow the back numbers. 你可以借过期期刊.
may的否定形式:may not,但表示“不可以”或“禁止”时用must not eg: —May I watch TV now?我现在能看电视吗? —No, you mustn’t. 不,你不可以看. may还可以表示推测.eg:
There may be a few copies left in the bookstore.书店里可能还有几本. 5. might: may的过去式.用于推测时语气更加不肯定. eg: He might be at home today. 今天他可能在家.
6. must:必须.表示说话人的主观意志. have to表示客观需要;且比must有更多的时态形式. eg:
We must hand in our papers today.(主观看法)今天我们必须把卷子交上去. We have to get there before dark. (客观需要)天黑前我们必须到达那里. 对must引导的问句作否定回答时常用needn’t或don’t have to. eg: —Must I leave now?我现在必须走吗?
—No, you needn’t. (You don’t have to.)不,你不必.
7. shall:在疑问句中用于第一、三人称,表示征求意见或请求指示. eg: Shall I turn off the power?要不要我把电源切断? shall用于二、三人称表示命令、警告或允诺. eg: You shall be punished.你会受到惩罚的.
8. should:应该;ought to:义务、责任,语气稍重一些. eg: You should keep your promise. 你应该遵守你的诺言. We ought to help them when they are in trouble. 当他们有麻烦时,我们有责任帮助他们. 9. will:表示意愿 eg:
I will stop smoking.我要戒烟.
在疑问句中用于第二人称表示询问和请求. eg: Will/Would you please do me a favor?请帮帮忙好吗? 10. would: will的过去式,表示提出请求时语气较委婉. (1)在下面的句型中要用would,不用will.
Would you mind if I smoke a cigarette?我能抽一支烟吗?
Would you like to have a look at the house?你想看一看这房屋吗? (2)但在否定句中用will,不用would. eg: Won’t you sit down?你不坐一会儿吗?
(3)would可表示过去的习惯动作,可和used to互换,但used to表示现在不存在的习惯. eg:
When I was in Shanghai, she would tell me about the great changes there.当我在上海时她总是对我讲上海的巨大变化.
He used to drink alcohol, but now he drinks beer. 他过去喝白酒,但现在喝啤酒.
11. need与dare: 既可作情态动词也可作实义动词.一般在肯定句中作实义动词,在否定句和疑问句中作情态动词. eg:
Dare you go out alone at night?(dare是情态动词)晚上你一个人敢出去吗? The bike needs to be repaired.(need是实义动词)这辆自行车需要修理. 12.情态动词+have done表示对过去发生事情的推测.
(1)may/might have done表示“可能”might语气婉转.但主句中动词为过去时态,一定要用might. eg:
He said she might have missed the train. 他说她可能没赶上火车. (2)could have done表示“本来能够做某事”. eg: You could have succeeded. 你本能够成功.(事实是失败了.) (3)can’t/couldn’t have done表示“不可能发生某事”. eg: He thought his son couldn’t have taken all the tablets. 他认为他儿子不可能把药全都吃了.
(4)must have done表示“肯定发生了某事”. eg:
The windows look bright and clean today. Some must have cleaned them. 窗子这么干净明亮,一定有人擦过了.
(5)should/ought to have done表示“本应该做某事”. eg:
You should have kept the matches under lock and key.你应该把火柴保管好.(带有责任的意思) (6)needn’t have done本没有必要做某事. eg: There was plenty of time, so she needn’t have hurried. 时间很充裕,她本不用匆匆忙忙的. 13.某些固定结构中情态动词用法.
(1)had better+动词原形,否定形式为:had better not do„ eg: You had better go to school at once.你最好立刻去上学.
(2)would rather+动词原形,否定形式为:would rather not do„ eg: I would rather do it right away. 我宁可立即就做.