主动语态与被动语态：
英语动词有两种语态，即主动语态(The Active Voice)与被动语态（The Passive Voice)。主动语态表示主语是动作的执行者;被动语态表示主语是动作的承受者。
e.g.
1.They make trains in Zhuzhou .
Trains are made in Zhuzhou.
2.The farmers grow cotton every year.
Cotton is grown by the farmers every year.
(一)一般现在时被动语态的构成：
am/is/are+及物动词的过去分词
动词过去分词的构成规则（与动词过去式构成规则一样）：
1、一般在动词原形末尾加-ed，looked played
2、结尾是e的动词加-d ， lived used
3、末尾只有一个辅音字母的重读闭音节词，先双写
这个辅音字母，再加-ed， planned tripped
4、结尾是“辅音字母+y”的动词，先变“y”为“i” ， 再
加-ed ， study---studied， carry---carried
不规则动词的过去分词要牢记
写出下列动词的过去式，过去分词：
1、speak （spoke spoken）
2、use used used
3、make made made.
4、write wrote written
5、grow grew grown
6、plant planted planted
7、produce produced produced
8、ask asked asked
9、plan planned planned
10、send sent sent
11 、 build built built.
12、invite invited invited
(二)一般过去时被动语态的构成：
was/were+及物动词的过去分词
e.g 1、The bridge was built last year.
2、It was used in the old days.
3、The PRC was founded
on October1，1949.
(三)含情态动词的被动语态构成：
情态动词（can/may/must/should）+be+及物动词过去分词
e.g 1、This bike can be repaired.
2、The tree must be put straight in the hole.
3、The classroom should be cleaned every day.
(四)现在完成时的被动语态构成：has / have + been + 及物动词的过去分词
This book has been translated into many languages.
Many man-made satellites have been sent up into space by many countries.
(五)一般将来时的被动语态构成：will+ be + 及物动词的过去分词
A new hospital will be built in our city.
Many more trees will be planted next year.
(六)现在进行时的被动语态构成：am / is / are + being + 及物动词的过去分词
Tom is mending my bike now.→My bike is being repaired by Tom now.
They are planting trees over there. →Trees are being planted over there by them.
主动语态变被动语态的步骤：
1、主动语态的宾语变为被动语态的主语；
2、主动句的谓语动词变为被动结构；
3、主动句的主语变为被动句的宾语，由by 引出，当不强调动
作的执行者时，常省略。
把下列的句子变为被动语态的句子：
1、They speak English in Canada .(English….)
2、People use wood for making tables. （wood….）
3、The make computers in the USA.（Computers…）
4、They grow rice in South China.（Rice…）
使用被动语态应注意的几个问题
1. 不及物动词无被动语态
What will happen in 100 years.
The dinosaurs disappeared about 65 million years ago.
2. 有些动词用主动形式表示被动意义。
This pen writes well.
This new book sells well.
3. 感官动词或使役动词使用省略to的动词不定式，主动语态中不带to ，但变为被动语态时，须加上to
例：make somebody do something →somebody+ be +made to do something
see somebody do something →somebody +be +seen to do something
A girl saw my wallet drop when she passed by.
→My wallet was seen to drop by a girl when she passed by.
4. 如果是接双宾语的动词改为被动语态时，直接宾语(物)作主语，那么动词后要用介词，这个介词是由与其搭配的动词决定。
He gave me a book. →A book was given to me by him.
He showed me a ticket. →A ticket was shown to me by him.
My father bought me a new bike. →A new bike was bought for me by my father.
5. 一些动词短语用于被动语态时，动词短语应当看作一个整体，而不能丢掉其中的介词或副词。
We can’t laugh him. →He can’t be laugh by us.
He listens to the radio every day. →The radio is listened to by him every day.
6.含有复合宾语的主动句，宾补不变。
（1） 将宾语变为主语，宾补不变。
如：They call her Xiao Li. →She is called Xiao Li.
He left the door open. →The door war left open by him.
（2） make, let, have, hear, watch, see, feel, notice. help动词后变做宾补的不定式一般不加to，变为被动，必须加to .
如：My brother often made me do this and that when I was young.
→I was often made to do this and that by my brother when I young.
I heard her move about in her room upstairs last night.
→She was heard to move about in her room upstairs last night.
7)有些词如want, need, require和 be worth后面， v-ing形式为主动，意义为被动。
如：The room needs/wants/requires cleaning.
The book is worth reading.
8)谓语动词是以下时，无被动。
happen, belong to, suit, fit(适合), have, let, join, fall, last（延长）,cost（花费）
break out（爆发）appear, burst out(迸发)，hold(容纳)，lack（缺乏），agree with（同意）.
被动语态结构与SVC(动词－ed形式作表语)结构的区别
被动语态表示动作，句子主语为动作的对象，SVC结构表示主语的特点或所处的状态，其中的过去分词相当于形容词，be只有一般时态和完成时态。被动结构的时态一般要与相应的主动结构一致。
下面把这两种结构作一比较：
1、The library is usually closed at 6.图书馆通常六点关门。(被动语态)
The library is now closed.图书馆关门了。(SVC结构)
2、The bridge was completed in 1968.桥是1968年建成的。(被动语态)
The bridge is completed.桥已修好。(SVC结构)
3、The glass was broken by my sister.玻璃杯是我妹妹打破的。(被动语态)
The glass is broken.玻璃杯破了。(SVC结构)
