含if的真实条件句和虚拟条件句

一、含if的真实条件句和虚拟条件句
1、在英语中，语气是动词的一种形式，用来表示说话人的意图或态度。

英语的语气有三种：陈述语气（表示所说的话是事实），祈使语气（表示所说的话是请求或命令）和虚拟语气（表示所说的话只是一种主观的愿望或假设或建议等）。

如果所表示的条件是真实的，或者完全有可能实现的，叫真实条件句，主句和从句的谓语都用陈述语气。

2、在含有were, had, 或者should 等词的虚拟条件句中，可以省略if, 将were, had或者should这些助动词放在句首。

二、被动语态
1. 被动语态的基本时态变化
被动语态通常为十种时态的被动形式, 被动语态由be＋过去分词构成，be随时态的变化而变化。

以do为例，各种时态的被动语态形式为：
1) am/is/are +done (过去分词) 一般现在时
2）has /have been done 现在完成时
3）am/is /are being done 现在进行时
4）was/were done 一般过去时
5）had been done 过去完成时
6）was/were being done 过去进行时
7）shall/will be done/ be going to be done/ be about to be done/ be to be to done一般将来时
8）should/would be done/was\were going to be done/ was\were about to be done/was\were to be to done过去将来时
9）shall/will have been done 将来完成时（少用）
10）should/would have been done 过去将来完成时（少用）
2. 被动语态的特殊结构形式
1)带情态动词的被动结构。

其形式为：情态动词＋be＋过去分词。

2) 有些动词可以有两个宾语，在用于被动结构时，可以把主动结构中的一个宾语变为主语，另一宾语仍然保留在谓语后面。

通常变为主语的是间接宾语。

例His mother gave him a present for his birthday. 可改为He was given a present by his mother for his birthday.
3) 当“动词+宾语+宾语补足语”结构变为被动语态时，将宾语变为被动结构中的主语，其余不动。

例Someone caught the boy smoking a cigarette. 可改为The boy was caught smoking a cigarette.
4）在使役动词have, make, get以及感官动词see, watch, notice, hear, feel, observe等后面不定式作宾语补语时，在主动结构中不定式to要省略，但变为被动结构时，要加to。

3. 非谓语动词的被动语态
v.+ing形式及不定式to do 也有被动语态(一般时态和完成时态) 。

3、谓语动词的主动形式表示被动意义
1）.英语中有很多动词如break，catch，clean，drive，lock，open，sell，read，write，wash 等，当它们被用作不及物动词来描述主语特征时，常用其主动形式表达被动意义,主语通常是物。

2）. 表示“发生、进行”的不及物动词和短语，如：happen, last, take place, break out, come out, come about, come true, run out, give out, turn out等以主动形式表示被动意义。

3）. 系动词没有被动形式, 但有些表示感受、感官的连系动词feel, sound, taste, book, feel等在主系表结构中常以主动形式表示被动意义。

4、非谓语动词的主动形式表被动意义
在某些句型中可用动名词和不定式的主动形式表被动意义。

1）．在need，want，require, bear等词的后面，动名词用主动形式表示被动意义，其含义相当于动词不定式的被动形式。

2）．形容词worth后面跟动名词的主动形式表示被动含义，但不能跟动词不定式；而worthy后面跟动词不定式的被动形式。

英语被动语态练习题.
一. 用正确的时态语态填空
1.she ________ (tell) the good news as soon as it arrived.
2.A lot of work ________(do) for the poor kids in the past few years.
3.The book _______ (write) by the young girl.
4.The fruit from Taiwan ________ (sell) well.
5.We must __________ (allow) to grow hair long.
6.My shoes need __________ (mend).
7.A new building __________(build) at our school now.
8.An earthquake __________(happen) at midnight.
9.The students were made _________(hand) in their homework.
10.I don't believe you've already finished reading the book which ________(lend) to you this morning！
11.- What's that noise? - Oh,I forgot to tell you.The new machine ________(test).
puters ________________(use) very widely in the world now.
13.Silk __________(produce) in Hangzhou and Wool in Qinghai.
14.Another bridge ________(build) over the river and it _________(come) into use at the end of this year.
15.The thief _________(catch) and ________(send) to the station ten minutes ago.
16.In the past few years a lot of buildings _________(set) up in our city.
17.All the tickets __________(sell) out when we got to the cinema.
18.“The exercises must _________(do) right away.” He said.
19.Wood can ________(make) into a lot of things.
20.Nothing can save him. What can be done ____________(do).
二．把下列句子变成被动语态或变为主动语态。

1. My brother opens the windows every morning.
2. She didn’t clean the room this morning.
3. Do they speak English in America?
4. The actor was loved by the young people.
5. The clothes aren’t washed by her.
6. What was found by them?
7. Bob gave her an interesting book.
8. He bought his children some pencils.9. Everyone calls me Xiao Wang.
10. Mary is making a doll.11. She cannot compose such fine music.
12. My mother was cutting down the tree.13. He hasn’t received the letter.
14. Somebody was cleaning the room when I arrived.
15. We believe him to be a great scholar.16. we often heard him singing.
17. My father made me go there alone.18. Everybody will know the truth soon.。