内容正文:
人教版-九上-Unit 7-重点语法
知识元
语法:被动语态III
知识讲解
含有情态动词的被动语态
一、其结构为:情态动词+be动词+过去分词
常考的情态动词有:can/could; may/might; must; need; should
As a student, your homework must be finished by yourself.
Waste paper shouldn’t be thrown everywhere.
二、含有情态动词的被动语态的句子结构
句式
结构
例句
肯定句
主语+情态动词+be done (+ by +宾语)
The work should be finished by ten.
否定句
主语+情态动词+not+be done (+ by +宾语)
Those books mustn’t be taken out of the library.
一般疑问句
情态动词+主语+be done (+ by +宾语)
May these rooms be cleaned tomorrow?
特殊疑问句
特殊疑问词+情态动词+主语+be done (+ by +宾语)
When should these books be sent to the children in mountain areas?
注:1. 括号中by+宾语 可以省略
2. 含有情态动词的被动语态的一般疑问句的回答应保留原情态动词,
但must表“必须”时,其否定回答应用needn't;而need表示“必要;必须”时,其肯定回答应用must。
—Must all the rooms be tidied up? 所有的房间都必须整理好吗?
—Yes, they must. 是的,必须整理好。
—No, they needn't. 不,不必都整理好。
—Need he be operated on at once? 他需要立即手术吗?
—Yes, he must. 是的,他必须。
—No, he needn't. 不,他不需要。
三、含有情态动词的主动句与被动句之间的转换
主动句:She must clean her room ev