英语的语态有主动语态和被动语态两种。当主语是动作的执行者时，用主动语态;主语是动作的承受者时，即谓语动词与主语在逻辑上有“动宾关系”时，用被动语态。被动语态一般由“助动词be+过去分词”构成，其中be有时态、人称和数的变化。如：

1. Visitors ________ not to touch the exhibits. (全国卷)

A. will request B. request

C. are requesting D. are requested

【分析】答案选D。visitors是request这个动作的承受者，即request与visitors是动宾关系，要用被动语态，应由“be+过去分词”构成，只有D符合。

2. In some parts of the world, tea ________ with milk and sugar. (全国卷)

A. is serving B. is served

C. serves D. served

【分析】答案选B。tea是serve这个动作的承受者，即serve与tea是动宾关系，用被动语态，被动语态就应由be与serve的过去分词构成，只有B正确(from www.nmet168.com)。

3. according to the art dealer, the painting ________ to go for at least a million dollars. (四川卷)

A. is expected B. expects

C. expected D. is expecting

【分析】答案选A。the painting是expect (预料、估计)这个动作的承受者，即expect与the painting是动宾关系，要用被动语态，只有A正确。

4. I ________ ten minutes to decide whether I should reject the offer. (全国卷)

A. gave B. was given

C. was giving D. had given

【分析】答案选B。I是give这个动作的承受者，即give与I是动宾关系，选B。

5. All the employees except the manager ________ to work online at home. (广东卷)

A. encourages B. encourage

C. is encouraged D. are encouraged

【分析】答案选D。all the employees是encourage的承受者，要用被动语态，排除A和B。句子的主语是all the employees，而不是the manager，排除C。

6. A library with five thousand books ________ to the nation as a gift. (全国卷)

A. is offered B. has offered

C. are offered D. have offered

【分析】答案选A。a library是offer的承受者，要用被动语态;又因主语(library)是单数，只有A正确。with five thousand books是a library是定语。

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