2010年12月英语四六级考试必备核心语法(14)

　　(四)被动语态的用法

　　1、不知道或没有必要指出动作的执行者。换个说法，有一件事情不知道是谁干的或者不想说出是谁干的，这时就用被动语态。例如：

　　I felt a littlie nervous when I was being interviewed. 我接受面试的时候，有点紧张。

　　These fighters are imported from Russia. 这些战斗机是从俄国进口的。

　　That place has been turned into a swimming pool. 那个地方已被变成游泳池。

　　2、说话或发表意见时，为了显得客观公正，也常用被动语态

　　He’s said/believed/reported to be in the U. S. A. 据说/据信/据报道他在美国。

　　还有下列常用句型(that后面跟句子)：

　　It is said that……. 据说

　　It is reported that……. 据报道

　　It is hoped that……. 希望

　　It is believed that……. 人们相信

　　It is announced that……. 据宣布

　　it is (well) known that……. 众所周知

　　It has been decided that……. 已经决定

　　It is supposed that……. 人们认为

　　It is suggested that……. 有人建议

　　It must be remembered that……. 务必记住

　　It is taken for granted that……. 被视为当然

　　(五)主动句变被动句的注意事项

　　一是时态不能改变;二是变为被动语态后，谓语动词要和被动语态的主语在人称、数上保持一致。还要作如下变动：把主动语态的宾语变为被动语态的主语;主动语态的主语放在by的后面，组成介词短语，再把这个介词短语放在被动语态的谓语动词之后。在动作的执行者无须说明或不必要强调时，by短语可以省略。例如：

　　They will open a new supermarket there soon. 他们很快将在那里开办个新超市。

　　A new supermarket will be opened there soon. 一个新超市不久将在那里开办。

　　The doctor gave two lectures in English. 那位医生用英语讲了两次课。

　　Two lectures were given by the doctor in English. 由那位医生用英语讲了两次课。

　　Somebody has warned us to be careful of rats. 有人警告我们要当心老鼠。

　　We have been warned to be careful of rats. 我们受到警告，要当心老鼠。

　　如果主动语态有两个宾语(直接宾语和间接宾语)，变为被动语态时，可将其中任何一个宾语变为主语，另一个不变。但较常见的是将间接宾语变为被动语态的主语。

　　The reporters asked the president some questions. 记者们问了总统一些问题。

　　The president was asked some questions by the reporters. ( 变间接宾语为主语)

　　Some questions were asked the president by the reporters. (变直接宾语为主语)

　　We have given him a job. 我们已给了他一个工作。

　　He has been given a job. (变间接宾语为主语)

　　A job has been given (to) him. (变直接宾语为主语)