条件状语从句讲解(基础版本)

条件状语从句讲解

――if引导的条件状语从句（注意&练习）在句子中做条件状语的从句称为条件状语从句。可置于句首、句尾，有时还可置于主语和谓语之间。引导条件状语从句的连接词有：if ,unless,as/so long as等

1.if引导的条件状语从句

表示在某种条件下某事很可能发生。

If we pay much attention to the earth, we'll have a better world.

如果我们多关爱地球，就会拥有一个更美好的世界

If it rains tomorrow, what shall we do?

如果明天下雨，我们怎么办？

注意：if还可以引导虚拟条件句，表示不可实现的条件，从句中多用一般过去时或过去完成时。What would happen if there were no water ?

如果没有水会怎样？

2.unless引导的条件状语从句

unless的意思是如果不，除非。可与if...not互换。

You will fail in English unless you work hard.

你英语考试会不及格的，除非你更加努力。

3.as /so long as引导的条件状语从句

as /so long as意思是“只要”

So long as you're happy,i will be happy.

只要你高兴，我就高兴。

4.once引导的条件状语从句

once引导的条件状语从句，意为“一旦...，就”，从句可置于主句前或后

Once you begin,never stop.

一旦开始，就绝不要停止

Maths is easy to learn once you understand the rules.

一旦你理解了规则，数学就不难学了。

提示：在条件状语从句中，用一般现在时代替一般将来时，用一般过去时代替过去将来时。

If the weather is bad next week, we'll put off the climbing.

如果下周天气不好，我们将推迟爬山。

Father told me if I worked hard he would buy me a gift.

爸爸告诉我，如果我努力学习，他会给我买一份礼物。

注意：

学习" if " 引导的条件状语从句的用法,现在总结一下:

if 条件句不一般,几个要点记心间;

条件句,放在前,逗号要放句中间。

条件句表可能，主句多用将来时；

条件句表事实，主句常用现在时。

在if 引导的条件状语从句中，如果从句谈论的是一个有可能发生的事实及其产生的相关的结果，主句用一般将来时态，从句用一般现在时态。如：

We can walk there if we can't find a bus .

If it rains tomorrow ,we will not go to the zoo.

What will you do if you find a panda in danger.

如果if 条件句谈论的是重复发生和预示要发生的情景和事件，则主从句大多用一般现在时态。如：If bears are in danger ,they attack people.

在if 引导的条件状语从句中，if 和条件句位置灵活，可直接放在主句后面，若if 条件句放句首，从句后面要加逗号，和主句隔开。还要注意前后时态一致原则

if 条件状语从句的时态练习

一．在正确的答案下划一条线。

1.Daina ( will go/go/goes) to Europe if she (will pass/pass/passes) the exams .

2. The graduates (will teach/teach/teaches) in the poor village if the Ministry of Education (will agree/ agree/agrees) soon.

3. If there (will be/ are/is) a car accident, they (will call/call/calls) 110 for help at once.

4. If it (won’t/don’t/doesn’t/ isn’t) rainy, we (will take/ take/takes) walk outside.

5. If a UFO (will land/land/lands) in front of me, I (will go/go/goes) in to look for the alien.

6. If he (will have/have/has) money, he (will bulid/build/builds) a science lab.

7.Don’t wait for me if I (am/ will be) late.

8.They (won’t/don’t) go to the beach if it (will rain/rain /rains).

9. I (will call/ call) you if he (will stay/stay /stays) at home.

10. Mr Smith (will let/ let/lets) you know if he (will need/ need/ needs) help.

11. (Will / Do/ Does) he visit the museum if he (won’t / don’t/ doesn’t) get tired?

12. Where (will/ do/does) they live if they (will miss/ miss/ misses) the bus?

状语：状语是句子的重要修饰成分。状语是谓语里的另一个附加成分,它附加在谓语中心语的前面,从情况,时间,处所,方式,条件,对象,肯定,否定,范围和程度等方面对谓语中心进行修饰或限制。用来说明地点、时间、原因、目的、结果、条件、方向、程度、方式和伴随状况等。

状语一般由副词、介词短语、分词和分词短语、不定式或相当于副词的词或短语来担当。其位置一般放在句末，但也可放在句首或句中。

副词是一种用来修饰动词,形容词,副词或全句的词,说明时间,地点,程度,方式等概念。

1.副词一般在句子中做状语．

He speaks English very well. 他英语说得非常好.中的very是程度副词，用来修饰well。very well是修饰speak的程度状语。

He is playing under the tree.他在树下玩儿.中的under the tree 是地点状语.

2. 不定式在句子中可以作目的状语。

I come specially to see you.我专门来看你.

3.介词短语

Ten years ago, She began to live in Dalian.

The boy was praised for his bravery.

4.从句作状语

When she was 12 years old, she began to live in Dalian.

If I am not busy tomorrow, I will play football with you.

5.分词作状语

Having had a quarrel with his wife, he left home in a bad temper。

Inhibited in one direction, it now seems that the Mississippi is about to take another.

在复合句中，由从句表示的状语叫做条件状语从句。它可以用来修饰主语中的动词.形容词.副词等。根据它表达的意思，状语从句可以分为时间状语从句，原因状语从句，条件状语从句，比较状语从句，目的状语从句，结果状语从句和让步状语从句等。

定义

由连接词if或unless引导的状语从句叫做条件状语从句。（注意：在含有条件状语从句的复合句中，如果主句是一般将来时态，从句要用一般现在

是[主将从先原则])在英文中，条件是指某一件事情实现之后（状语从句中的动作），其它事情（主句中的动作）才能发生，通常译作“假如，如果，除非”。

引导词：

①常用引导词： if , unless

②特殊引导词: as long as（除非；只要），supposing（假设），on condition that（条件是），in case（如果）

条件状语从句的位置

可放在句首或句尾，放在句首时常用逗号与主句隔开。

If 引导词用法

if 引导的条件句有：真实条件句和非真实条件句两种:

1.真实条件句：表示在某种条件下某事很可能发生。

如:

If you ask him, he will help you.

如果你请他帮忙,他会帮你的。

If you fail in the exam, you will let him down.

如果你考试不及格,你会让他失望的。

If it rains tomorrow, we won’t go on a picnic.

如果明天下雨，我们就不去野餐。

注意：在含有条件状语从句的复合句中，表示将来时态，主句是态，从句要用[原则]，并且，切记紧跟着if的那句话是从句。）

2.非真实条件句是的一种，表示与事实相反，不可实现的条件或根本不可能存在的条件,也就是一种虚拟的条件或假设,从句多用一般过去时或过去完成时。

如: If I were you, I would invite him to the party.

如果我是你,我会邀请他参加聚会。

I would have arrived much earlier if I had not been caught in the traffic.

如果没有堵车,我会到的早一点儿。

If I were you, I would go with him.

如果我是你,我会和他一起去的。

unless引导词用法

固定搭配： unless = if...not 除非,若不,除非在……的时候

You will fail to arrive there in time unless you start earlier. If you don’t start earlier, you will fail to arrive there in time.如果你不早点动身,你就不能及时赶到那儿。

Unless it rains, the game will be played.

If it dosen't rain，the game will be played.

除非下雨,比赛将照常进行。

Let's go out for a walk unless you are too tired.

If you are not too tired, let's go out for a walk.

经典语句：If it dosen't rain tomorrow,we will go to the zoo.

条件状语从句就是用以表示“在某种条件下,会……”

由as (so) long as, in case引导。

So long as you’re happy, it doesn’t matter what you do.

只要你高兴，你做什么都没有关系。

You may borrow my book as long as you keep it clean.

只要你保持书的清洁，你就可以把我的书借去。

Take your umbrella in case it rains.

带着你的伞吧，以防下雨。

完成下列句子

1。如果你请求他，他会帮你的

If you ___him, he ___ ____you

2。如果她早点儿起床，就有时间在家里吃早餐

If she____ ____a little earlier, she’ll have time to eat breakfast at home.

3。如果你参加聚会，你将会过得很开心。

If you____ the party ,you_____ ____ a great time.

4。如果明天下雨，我们将不去野餐

If it ____tomorrow, we _____ _____ for a picnic.

5。如果你经常听英文歌，你将会喜欢英语

If you often _____ ____English songs,you___ ___English.

1、 ask will help

2、 gets up

3、 join will have

4、rains won’t go

5、 listen to will like

状语从句语法讲解

咼中英语状语从句 定义: 在句中作状语的从句是状语从句，修饰主句中的动词、形容词或副词等.状语从句由从属连词引导，从属连词在句中不充当句子成分，只起连接作用，状语从句放在句首时，要用逗号，放在句 尾时不用. 分类 根据意义上的不同，状语从句可分为：①时间状语从句②地点状语从句③原因状语从句④ 目的状语从句⑤条件状语从句⑥结果状语从句⑦让步状语从句⑧方式状语从句⑨比较 状语从句三、时间状语从句主句是一般将来时，时间状语从句用一般现在时表将来；主句是—过去将来时，从句用一般过去时表示过去将来时；主句是一般过去时忆：“主将 ，从句用一般过去时.记从现” (一)引导时间状语从句的连词有：As，whe n (whe never)，before，after，as soo n as，un til (till)，since，every time，once. | （二）、具体应用1）“while ”主、从句动作或状态同时发生.用while引导的从句用延续性 动词，常表示较长的时间或一个过程.记忆：While 后用进行时.While we were having supper， all the lights went out. Please kee p quiet while others are study in g」 While I was writing letters last night，he was watching TV. 2 ）When 表示“就在”的时候"， while 意为反而，可是，表示转折.One evening Beethoven was walking in a street，when he sudde niy stopped outside a little house. 3）When ever无论什么时候，随时 1.When ever some one throws in some rubbish，the truck p roduees a pi eee of music. 每当有人扔进一些垃圾时，它（汽车）就放一段音乐 2.When ever we' re in trouble，they will help us. 3.I go to the theatre, whe never I am free. https://www.wendangku.net/doc/7c9634007.html,e and see me whe never you want to.你随时来看我 4) till和until(表示"直到” ”)句首多用until | 1在肯定句中表示“直到”为止”，主句谓语动词要用延续性动词 I was wait ing un til/till he arrived. 2、在否定句中表示“直到，，才”主句谓语动词常用终止性动词，这时until和till常被before 替换. I did n' t leave till/un til she came back. 5) si nee:主句用完成时，从句用一般过去时，si nee引导的从句间或可用现在完成时 It is two years since I have studied En glish. 1.We have known each other si nee we were childre n. 2.We have bee n friends （ever sin ce） since we met at school. 3.It is ”（一段时间）+since+—般过去时态句子 It is two years since my sister married. I

英语语法专题条件状语从句(讲解+练习,无答案)

中考语法专题条件状语从句（讲解+练习，无答案）
条件状语从句
常用引导词：if, unless, as/so long as
1、if 从句 + 祈使句，“如果……，就……”
If you do not feel well, please go to see the doctor. 如果你感觉不舒服，就去看医生 吧。
If you want to know more about it, call now. 如果你想了解更多内容，现在就打电话 吧。
Make sure you visit the Science Museum if you ever go to London. 如果你去伦敦，一 定要去参观科学博物馆。
2、主将从现
If I start after dinner, I’ll finish it before I go to bed. 如果我晚饭后开始，睡觉前我就能 完成。
主句也可用“情态动词 + 动词原形” She may come with us if she arrives in time. 如果她来得及时，就可以和我们一起去。
3、if 条件状语从句和并列句的转换
Hurry up, or you’ll be late. = If you don’t hurry up, you’ll be late. Study hard and you will pass the exam. = If you study hard, you will pass the exam. 练习 （一）句型转换 1. Run fast, or you’ll be late for school. _______ you _______ _______ fast, you’ll be late for school. 2. You can buy the dictionary if you take enough money with you. Take enough money with you, _______ _______ _______ buy the dictionary. 3. If there is no air, none of us can live. None of us can live _______ _______.
4、unless “除非”
Don’t leave the building unless I tell you to. 不要离开大楼，除非我准许。 Unless you have finished your homework, I won’t allow you to watch TV. 除非你已完成 了作业，否则我是不会让你看电视的。 unless = if not You’ll be late if you don’t hurry. = You’ll be late unless you hurry. I can’t catch the train if I don’t get up early. = I can’t catch the train unless I get up early.
练习

比较状语从句讲解和练习题

比较状语从句： 状语从句指句子用作状语时，起副词作用的句子。比较状语从句是其中的一种，主要运用于形容词和副词的原级、比较级及最高级的句子之中。原级：as…as （和……一样），not so（as）…as …（和不一样）；比较级：more…than（更）；最高级：The most…in/of， the + 形容词+est…of/in。常用引导词：as（同级比较），than（不同程度的比较）；特殊引导词：the more … the more … ；just as …，so…；A is to B what /as X is to Y；no … more than；not A so much as B。 比较状语从句通常由as或than引起，这类从句和大多数状语从句不同，它们不修饰动词，而是修饰as，so，less，more等副词，或其他比较级的词，如taller， harder．在这里讨论它们，不是作为动词修饰语，而是作为一种状语从句。包含这类从句的句子通常为L，即从句在后：She is as tall as I（or me）． He works as hard as his brother（does）． He does not work as hard as his brother． He does not work so hard as his brother． No other men work as（or so） hard as his brother （does）．No other men work as hard as does his brother． She is taller than I（or me）． She is taller this year than（she was tall）last year． She is more shy than unsocial． She thinks more about her appearance than（she thinks about）her personality． She finds it easier to read than to write． She is not taller than I．（Both are tall．） She is no taller than I．（Both are short．）注意这两句话的区别。 I cannot persuade him any more than your persuade a pillar．（= I am unable to persuade him，just as you are unable to persuade a pillar．） I can forget her no more than she（forgets）me． Nothing is more dangerous than that you （should）make friends with him． I will help you rather than that you（should）have any trouble．rather than 而不是…

语法 状语从句讲解

语法状语从句 由从句担任的状语,在句子中可修饰谓语(或其它动词)、形容词、副词或就是整个句子,它可以用来表示时间、地点、原因、目的、结果、条件、方式、比较、让步等。 第一讲时间, 地点状语从句 时间状语从句:when, while, as, before, after, since , whenever until, till, by the time(注意时态) as soon as, had hardly…when, had no sooner…than,(on doing sth…) the moment, every time/ each time, the first time, once e、g: When he came, I had cleaned the classroom、 He didn’t stop working until his mother came bake、 He worked until his mother came back、 As soon as he returned, he bought a new flat、 He had no sooner returned than he bought a new flat He came to scene the moment he heard the news、 I thought her nice and honest the first time I met him、 Once he makes up your mind, he won’t change his mind、 It was two years before I met him again、= Two years passed before I met him again、注意点1、when引导的从句动词可以就是延续性的或短暂性的,while引导的从句中动词必须就是延续性的; while有时并不表示时间,而表示对比,表示“而”、“却”。 When I got home I found the door locked、 While(或When)we were working in the fields, it suddenly began to rain、 His pencil is red, while mine is yellow、 2、till与until not…until/till 解释为直到…才…主句动词一般就是短暂性的 …till/until… 解释为直到…为止主句动词一般就是延续性的一般情况下可以互换,但until可以位于句首,till则不能。 He worked until it was dark、 He didn’t stop working until it was dark、 Until it stops raining,the children can’t go out、 ＝Not until the rain stops can the children go out、 地点状语从句 引导地点状语从句的连词就是where 与wherever等。 I ll go wherever the people want me to go、(wherever＝to any place where) He works where his grandfather fought、(where＝in the place where) You must stay where you are、= You must stay in the place where you are、 Wherever you go, I go too、 Where there is water, there is life、(那儿有… 那儿就有… Where there is a will, there is a way、) 圈出其中的从句并翻译: 1.Whenever it is his turn to speak, he gets nervous、 2.Every time he comes, he always tells us something interesting、 3.When I get the news, I will let you know as soon as possible、 4.Once he makes a promise, he will never break it、 5.I had no sooner run into the school gate than I heard the bell for class、 6.I found the lost watch under a desk after the children had left for home、 7.He had to be called two or three times before he came down to dinner、 8.We didn’t notice anything wrong with the washer until we started using it、 9.The hunter made mark on the tree where he stops、 10.Wherever he is, he will find time to do some reading、

初中英语语法——If引导的条件状语从句(讲解及练习)

条件句从句主句 真实一般现在时一般将来时 情态动词+动原祈使句 非真实 一般过去时 be动词用（were） would/could+动原初中英语――条件状语从句（讲解&练习） Ⅰ条件状语从句的定义 Ⅱ条件状语从句的引导词 1.if引导的条件状语从句：表示在某种条件下某事很可能发生。 If we pay much attention to the earth, we'll have a better world. 如果我们多关爱地球，就会拥有一个更美好的世界 If it rains tomorrow, what shall we do? 如果明天下雨，我们怎么办？ 注意：if还可以引导虚拟条件句，表示不可实现的条件，从句中多用一般过去时或过去完成时。 What would happen if there were no water ? 如果没有水会怎样？ 2.unless引导的条件状语从句，unless的意思是如果不，除非。可与if...not互换。 You will fail in English unless you work hard. 你英语考试会不及格的，除非你更加努力。 3.as /so long as引导的条件状语从句：as /so long as意思是“只要” So long as you're happy,i will be happy. 只要你高兴，我就高兴。 Ⅲ条件状语从句的种类 Ⅳ条件状语从句的时态原则 用法例句 ①主句为一般将来时态，if从句用一般 现在时态（即主将从现）。We will stay at home if it rains tomorrow. 如果明天下雨，我将要呆在家。 ②主句中含有情态动词，if从句用一 般现在时态。If you finish your homework, you can go home now.如果你做完了作业，你现在可以回家了。 ③主句为祈使句，if从句用一般现在 时态。Don’t jump into the river if you feel very hot. 如果你感到很热，不要跳入河里。 ④主句为过去将来时，if从句用一般 过去时态（如果涉及到be动词， 一律都用were）。此时，表达的是和现实相反的推测，用虚拟语 气。If I were you, I wouldn’t do it like that.如果我是你，我就不会那么做的。 If you gave me some money, I would be very happy. 如果你给我一些钱，我就会很高兴的。 二、if 引导的条件状语从句 （1）“if 从句+祈使句”的句子。其实，if 作为一个连词，主句也可以是其他形式的句子。 例如：If you want to go, please let me know. (2)“祈使句 + and (or)+ 陈述句”

高考状语从句讲解

状语从句 一、时间状语从句 1、when, while, as 和whenever when 表时间点，时间段 while 表时间段；有“而”的意思 as “当……”,“一边……一边”，“随着……” whenever 每当，无论什么时候 It is cold when it snows. While there is life, there is hope. While we were speaking, he was reading newspaper. Just as Mrs Richards was entering the dinning-room, there was a knock on the front door. As we age, we trade strength for ingenuity, speed for thoroughness, and passion for reason. 随着年龄的增长，我们用力量换来了机敏，以速度换来了严谨，以热情换来了理智。 注：1)when还可作并列连词，其意义为“那时，这时”，相当于and at this/that time。常用于下列句式： sb.was doing sth.when...某人正在干某事就在这时…… sb.was about to/ going to do sth.when...某人正打算干某事就在这时…… sb.body has just done sth.when...某人刚干了某事就在这时…… 2)如果主句表示的是短暂动作，而从句用延续性动词的进行时态表示在一段时间内正在进行的动作时，when，while 与as可互换使用。如： When/While/As I was walking down the street，I came across an old friend of mine. 2、before/ after It will be five years before we meet again.五年之后我们才能见面。 After you think it over, please let me know what you decide. After her husband had gone to work, she sent her children to school. 3、until, till, not...until 1)肯定句：主句的谓语是延续性动词，主从句均为肯定式，意为“某动作一直持续到某时间点才停止”

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从句 从句按其在主句中的句法功能可分为三类: 即名词性从句、形容词性从句(即定语从句)和副词性从句(即状语从句)。 引导从句的词称作关联句. 一、名词性从句 引导这些名词性从句的关联词包括: 从属连词that, if, whether; 连接代词 who,whoever,whom,whomever,which,whichever,what,whatever,wh ose; 连接副词where, when, why, how。 其中, 从属连词只起连接作用, 在从句中不充当任何句法成分, 而连接代词和连接副词既起连接作用, 在从句中又充当一定的成分. That Owen should have married his cousin is not at all surprising. The fact is that he didn't go to the dinner party. I don't know if he will attend the meeting. Have you heard the news that Mary is going to marry Tom? 你听说玛丽要和汤姆结婚的消息了吗?(that引导同位语从句) [提示]

1. 在含有主语从句的复合句中, 为保持句子平衡, 常用it作形式主语,而将真正的主语从句置于句末. It's well-known that water is indispensable to life.(形式主语) 2. 为保持句子平衡, that引导的宾语从句也常用it代替, 而将真正的宾语从句置于主句句末。这常常出现在主句有形容词或分词作宾语补足语的情况下。 He made it quite clear that he preferred to live here. 3. 从属连词whether和if都作“是否…”解, 但if不可引导主语从句和表语 从句。whether可与or(not)连用, 而if不可以。 I don't know whether (if) she is at home. Whether she comes or not makes no difference. 4. that和what引导名词性从句的区别: that在从句中不充当成分,而what在从句中充当一定的成分, 如主语、表语、宾语等。that可省略, what则不可省。 He always means what he says. She suggested (that) he do it at once. 5. 同位语从句大多由从属连词that引导, 常跟在下列名词后面, 如fact, idea, opinion, news, hope, belief等, that不可省。同位语从句一般用来解释说明这些名词的具体含义和内容。 We are familiar with the idea that all matter consists of atoms. The news that we are invited to the conference is very encouraging.

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（一）状语从句概述 定义状语从句用作状语，是起副词作用的句子。 位置状语从句可以放在主句之前，也可以放在主句之后，时间、条件、原因和让步状语从句放在句首时需要用 逗号和主句隔开。 分类根据其作用可以分为时间、地点、原因、条件、目的、让步、方式和比较等状语从句。 作用它可以修饰谓语、非谓语动词、定语、状语和整个句子。 （二）状语从句详解 1. 时间状语从句 引导词用法示例 when 意为“当…的时候”。When 引导从句的谓语动词可以 是延续性动词，也可以是 瞬间动词。并且when有 时表示“就在那时”A liar is not believed when he speaks the truth.说谎者讲真话时也没有人相信。When he arrives, I’ll call you. When you laugh and smile, your body relaxes. while 意为“在…的时候，在…的 同时”。While引导从句的 谓语动词必须是延续性While I was standing at the window, I saw several boys running along the street.

的，发生时间较长，并强调主句和从句的动作同时发生（或者相对应）。While 有时还可以表示对比。While John was watching TV, his wife was cooking. as 意为“一边…一边…”。As 引导的动作是延续性的， 发生时间较短，一般用于 主句和从句动作同时发 生；as也可以强调一前一 后。The writer was angry as he was travelling on a train to London because someone had invaded his “space”. He smiled as he stood up. after 意为“在…之后”。表示主句 动作发生在从句动作之 后。主句与从句的动作时 间关系与before引导的从 句相反。With many hungry visitors waiting, don’t stay too long at your table after you have finished. If an early exit is necessary, you can leave after a scene is over. before 意为“在…之前”。引导的从 句不用否定形式的谓语， 并且当before引导的从句 位于主句之后，有时译成 “就，才”。当主句用将来时，You can’t watch TV before you finish your homework. Before it ended, the theatre was almost empty. My father had left for Canada

状语从句用法讲解和练习

第章状语从句 学习指导 状语从句在句子中作状语，用来修饰主句或主句的谓语。一般可分为九大类,分别表示时间、地点、原因、目的、结果、条件、让步、比 较和方式。尽管种类较多,但由于状语从句与汉语结构和用法相似,所 以理解和掌握它并不难。状语从句的关键是要掌握引导不同状语从句的常用连接词。现分别列举如下: 状语从句分九类： 在这一章节的学习中，要求同学们掌握各类状语从句基本概念，并能够灵活应用。 第一节时间状语从句 时间状语从句用一般现在时表示将来。连接时间状语从句的连接词有：2．when，while，as均可表示“当……的时候”。 when强调“特定时间”，表示主句谓语动词的动作与从句谓语动词的动作是同时发生的，或从句的动作发生在主句的动作之前；while表 示的时间是一段，而不是一点，as多用在口语中，强调“同一时间”或“一前一后”，有时还有“随着”的含义。 When spring came, he felt like a trip.春天来了，他想去旅游。 As spring warms the good earth，all flowers begin to bloom．(as有“随着”的含义) as, when, while都表示主、从句的动作或状态同时发生，但三者也有

区别。as和when引导的从句既可表示一点时间，也可表示一段时间，从句中的谓语动词既可以是持续性动词，也可以为短暂性动词，经常可以互换使用；while引导的从句通常表示一段时间，从句中宜用持续性动词作谓语。当从句中的谓语动词为持续性动词时，这三者可以通用（前面例句中已有体现），再如： 1 / 18 Mother was worried because little Alice was ill, especially as / when / while father was away in France.妈妈担心，因为小艾丽思病了，特别是当父亲远在法国的时候。 如果从句和主句要表示一个人的两个动作交替进行或同时完成时，则多用as，可译为“一边......，一边......”。例如： He looked behind from to time as he went.他一边走，一边不时地往后看。 As time goes on, it's getting warmer and warmer..随着时间的推移，天气变得越来越暖了。 I thought of it just as you opened your mouth.你一张嘴我就知道你要 说什么。（若表示两个短促动作几乎同时发生时，用as的场合多于when.） 当主从句之间表示转折或对比关系时，多用while, 不用as或when。如：

状语从句讲解和练习

状语从句 状语从句修饰主句/主句的谓语。一般有九大类：表示时间、地点、原因、目的、结果、条件、让步、比较和方式等。 时间状语从句 1. 用when引导：when表示“当……时候”。如： Things were different when I was a child. 我小时候情况与现在不同。 People breathe more slowly when they are asleep. 人睡觉时呼吸比较缓慢。 2. 用while引导：while表示“当……时候”。如： We must strike while the iron is hot. 我们要趁热打铁。 I went swimming while the others played tennis. 我去游泳，其余的人都打网球去了。 注意：while 所引导的时间状语从句中谓语动词必须是持续性的，不能是短暂性的。 3. 用as引导：as表示“当……时候”“随着”。如： He dropped the glass as he stood up. 他站起来时，把杯子摔了。 We get wiser as we get old. 随着年岁的增长，我们也变得聪明些了。 4. 用before引导：before表示“在……之前”。如： Turn off the lights before you go to bed. 睡觉前要关灯。 Before he went to university he was a worker. 上大学之前他是工人。 5. 用after引导：after表示“在……之后”。如： I will tell you after they leave. 他们走我再告诉你。 After you finish the letter show it to me．信写完后给我看看。 6. 用until / till引导：until / till表示“直到……”。如： He waited until she was about to leave. 他等着一直到她准备离开。 I watched him until he disappeared in the distance. 我瞧着他直到他在远处消失。 这类句型的主句动词通常只能是延续性动词，不能是终止性动词。但是，在否定句中，主句动词可以是终止性动词，此时构成not…ntil [till]…句式，意为“直到……才……”。如：

条件状语从句讲解(基础版本)演示教学

条件状语从句讲解 ――if引导的条件状语从句（注意&练习）在句子中做条件状语的从句称为条件状语从句。可置于句首、句尾，有时还可置于主语和谓语之间。引导条件状语从句的连接词有：if ,unless,as/so long as等 1.if引导的条件状语从句 表示在某种条件下某事很可能发生。 If we pay much attention to the earth, we'll have a better world. 如果我们多关爱地球，就会拥有一个更美好的世界 If it rains tomorrow, what shall we do? 如果明天下雨，我们怎么办？ 注意：if还可以引导虚拟条件句，表示不可实现的条件，从句中多用一般过去时或过去完成时。What would happen if there were no water ? 如果没有水会怎样？ 2.unless引导的条件状语从句 unless的意思是如果不，除非。可与if...not互换。 You will fail in English unless you work hard. 你英语考试会不及格的，除非你更加努力。 3.as /so long as引导的条件状语从句 as /so long as意思是“只要” So long as you're happy,i will be happy. 只要你高兴，我就高兴。 4.once引导的条件状语从句 once引导的条件状语从句，意为“一旦...，就”，从句可置于主句前或后 Once you begin,never stop. 一旦开始，就绝不要停止 Maths is easy to learn once you understand the rules. 一旦你理解了规则，数学就不难学了。

高中英语语法---条件状语从句讲解

条件状语从句 概念定义 由引导词if或unless引导的状语从句叫做条件状语从句。在英文中，条件是指某一件事情实现之后（状语从句中的动作），其它事情（主句中的动作）才能发生，通常译作“假如”。（注意：在含有条件状语从句的复合句中，表示将来时态，主句是一般将来时态,祈使句或情态动词，从句要用现在时态,[主将从现原则]（主将从现，将并非指将来时，还指表示将来含义的，跟着if后的那句话是从句。） 类型 条件状语从句 语法引导条件状语从句最常用的连词是if,由if引导的条件状语从句表示在某种条件下某事很可能发生。如： 1） If you ask him,he will help you. 如果你请他帮忙，他会帮你的。 2） If you fail in the exam,you will let him down. 如果你考试不及格，你会让他失望的 if引导的条件状语从句既可以将从句放前面也可以将从句放后面 （如果天下雨，我们就不玩了）If it rains,we will stop playing.‘ 转为We will stop playing if it rains. if引导的条件状语从句

另外，if从句还表示不可实现的条件或根本不可能存在的条件，也就是一种虚拟的条件或假设，从句多用一般过去时或过去完成时。如：If I were you,I would invite him to the party.如果我是你，我会邀请他参加聚会。I would have arrived much earlier if I had not been caught in the traffic.如果没有堵车，我会到的早一点儿。 那么，除了if之外，是否还有其他连词也可以引导条件状语从句呢?回答是肯定的，不仅有，还有很多。这些词由于出现的频率较小，且用法较复杂一些，所以不如if为大家所熟知罢了。下面就这些词的用法以例句的形式进行一下简单总结。 1、unless conj.除非，若不，除非在……的时候 You will fail to arrive there in time unless you start earlier.如果你不早点动身，你就不能及时赶到那儿。 Unless it rains,the game will be played.除非下雨，比赛将照常进行。 2、on condition(that)...在……条件下，如果 on condition (that)...引导的条件从句是主句事件发生的前提条件或唯一条件。 I can tell you the truth on condition that you promise to keep a secret.我可以告诉你真相，条件是你答应保密。 You can go swimming on condition (that) you don't go too far from the river bank.你只有在不远离河岸的条件下才可以下水游泳。 3、supposing conj.如果，假如 supposing引导的条件从句表示一种假设条件。 Supposing it rains,shall we continue the sports meeting?倘若下雨，我们的运动会还要继续举行吗? Supposing anything should go wrong,what would you do then?假如出了什么问题，你准备怎么对付?

初中英语条件状语从句语法点和习题

1．常用引导词：if（如果），unless（除非）。 I won’t go to the movies unless I am free tomorrow. 除非我明天有空，否则我不会去看电影。 2．条件状语从句的位置 可放在句首或句尾，放在句首时常用逗号与主句隔开。 it rains tomorrow, I will stay at home. = I will stay at home if it rains tomorrow. 如果明天下雨我就呆在家里。 3．if引导词用法 if引导的条件句有：真实条件句和非真实条件句两种。 真实条件句：表示在某种条件下某事很可能发生。 you ask him, he will help you. 如果你请他帮忙，他会帮你的。 4．unless引导词用法 固定搭配：unless=if...not 除非，若不，如果不 will fail to arrive there in time unless you start earlier. =If you don’t start earlier, you will fail to arrive there in time. 如果你不早点动身，你就不能及时赶到 那儿。 注意：在含有条件状语从句的复合句中，当主句是一 般将来时态，从句要用一般现在时（即主将从现原 则）。如果主句是祈使句或含有情态动词时，从句也 用一般现在时表将来。

you study hard, you will pass the exam. 1. I will send you an e-mail as soon as I ____ A___ in Canada. A. arrive B. arrived C. am arrivi ng D. will arrive 2. If there ____A___ no buying and selling of an imals, there ______ no killing in nature. A. is; will be B. will be; will be C. is; is D. will be; is 3. I’m waiting for my , I'll go shopping alone. A. If she comes B. If she won't come C. If she doesn't come 5. You can’t watch TV ___A_____ you finish your homework. A. unless B. if C. while D. as students _____A___ have a sports meeting this we

高中英语状语从句讲解和练习(含答案)之欧阳语创编

状语从句讲解和练习状语修饰动词、形容词、副词或整个句子。通常由副词、介词短语、动词不定式、分词和从句等担当。例如：1. Nat urally , our grandparents wer e pleased to get our phone call . (副词)2. We worked ha rd , from sunrise to sunset . (介词状短语)3. To help my d isabled aunt , I spend an ho ur working in her house ever y day . (不定式)4. Seen from a distance , the farmhouse l ooked deserted . (过去分词)

5. I know how to light a ca mp fire because I had done it before .（原因状语从句）状语的位置比较灵活，可以位于句首、句末或句中。enough用作状语修饰形容词和副词时必须后置。 状语从句主要用来修饰主句或主句的谓语。一般可分为九大类，分别表示时间、地点、原因、目的、结果、条件、让步、比较和方式。尽管种类较多，但由于状语从句与汉语结构和用法相似，所以理解和掌握它并不难。状语从句的关键是要掌握引导不同状语从句的常用连接词和特殊的连接词即考点。现分别列举如下:1．时间状语从句常用引导词：when, as, while, as soon as, while, before, after, since , ti ll, until特殊引导词：the minute, the moment, the sec ond, every time, the day，the instant, immediately , directly, no sooner … than, hardly …when, scarcely

条件状语从句讲解

条件状语从句 条件状语从句是一种比较常见的状语从句，引导条件状语从句最常用的连词是 if, 由if引导的条件状语从句表示在某种条件下某事很可能发生。如： If you ask him, he will help you. 如果你请他帮忙, 他会帮你的。 If you fail in the exam, you will let him down. 另外, if从句还表示不可实现的条件或根本不可能存有的条件, 也就是一种虚 拟的条件或假设, 从句多用一般过去时或过去完成时。如： If I were you, I would invite him to the party. I would have arrived much earlier if I had not been caught in the traffic. 如果没有堵车, 我会到的早一点儿。 其他的连词： 1.unless conj. 除非, 若不, 除非在…的时候 You will fail to arrive there in time unless you start earlier. 如果你不早点动身, 你就不能即时赶到那儿。 Unless it rains, the game will be played. 除非下雨, 比赛将照常实行。 2. on condition (that)...在……条件下, 如果; on condition (that)...引 导的条件从句是主句事件发生的前提条件或唯一条件。 I can tell you the truth on condition that you promise to keep a secret. 我能够告诉你真相, 条件是你答应保守秘密。 You can go swimming on condition (that) you don’t go too far from the river bank. 你只有在不远离河岸的条件下才能够下水游泳。 3. supposing conj. 如果, 假如 supposing引导的条件从句表示一种假设条件 Supposing it rains, shall we continue the sports meeting?