被动语态的构成形式是 Be + 动词的过去分词 + by sb.
- He is taken to USA by his mother. 他被他妈妈带到了美国。
- The information is needed by US. 单三的变化。
- The book was being read by him. 过去进行时的被动语态
- The computer has been used by her. 完成时的被动语态。
- The room will be cleaned. 将来时。
- Computer could have been used by them. 电脑可能被他们已经用过了。
- The information is needen.
- The book was read. 过去时
- The door has been opend. 过去分词， 完成时
- The book was being read. 过去进行时
- The computer has been used. 过去完成时
- The computer could has been used.
- The room will be cleaned. 将来时
- 被动语态可以和情态动词结合，情态动词放到被动语态的前面。情态动词 + be + 动词过去分词。 need + doing / to + 动词过去分词 表示"需要被怎么样..."。
- The food could be taken away. 可以被带走
- The food might be taken away. 能够被带走
- The food must be taken away. 必须被带走
- The food should be taken away. 应该被带走
- The food needs taking away. 需要被带走
- The food had better be taken away. 最好被带走
- Book used to be returned in two days. 常常在两天内被还回去。
- The room may be cleaned.
- The door must be locked.
- The house should be furnished.
- The tree had better be watered now.
动作的行为者不分明，或不重要，或上下文中提到了行为者时，“by + 行为者”可以省略。
- The information is needed.
- The book is being read.
- The door was opened.
- The door is opend. 门被打开了。 一般过去时。
- The book is being read. 正读着。 进行时
- The computer has been used. 已经被用了。 完成时
- The pencil had been sharpened. 已经被削尖了。 完成时
被动语态的一般疑问句： 助动词 + 主语 + 其他动词 + 动词过去分词
- Is the information needed by him? -yes,it is./ no,it isn't.
- Has the computer been used by her? -yes,it has./no it hasn't
- Will the room be cleaned? -yes,it will./ no, it won't.
被动语态的特殊疑问句： 疑问词 + 助动词 + 主语 + 其他助动词 + 动词过去分词
- The information is needed by them.- what is need by them?
- The girl is taken to ShangHai. - where is the girl taken?
- The book has been read three times. - how many times has the book been read?
- Is the book being read by her? 他正在读那本书吗？
- Has the computer benn used by them? 他们用过那太电脑么？
- How often is the English class taken? 英语课多长时间上一次？