双重被动句
句型[主语+被动式谓语+被动不定式+其他]
1.The date is expected to be announced soon.
2.The gate was ordered to be closed at nine oclock.
3.The books are not allowed to be taken out of the room.
4.These arms are supposed to have been used by partisans during the anti|Japanese war.
5.The task is reported to have been completed yesterday.
6.The instruments are supposed to be used only by skilled workers.
[注] H. W. Fowler 说过，双重被动式，从文体学看法来看是应该尽可能防止，由于从表面看来容易为类似的假象所混淆。如：(错) The house was begun to be built. 不是房屋开始而是房屋的建造开始。下列动词不适合于本句型：attempt, decide, promise, seek, begin, hope, intend, propose, purpose, threaten等。
不可说：The work was attempted to be done quickly. 应当说：An attempt was made to do the work quickly.
不可说：He has been decided to be helped. 应当说：It has been decided to help him. It has been decided that he should be helped.
[附注]主动语态与被动语态互相转换时应注意的什么时间事情。
1)基本转换公式：省略。
2)转换时一般不能变更动词的时态。另下列各时式不可以用于被动句中。
1. 以后进行时 2. 目前完成进行时 3. 以后完成进行时 4. 过去完成进行时
3)被动句中by后接 us, you, them, one时，by短语可以省略。
4)祈使句中用被动式谓语极少见，以下各句可说是例外：Please be seated. Be trusted rather than feared.
通常情况用let帮助构成祈使句的被动语态。
Do one thing at a time. Let one thing be done at a time. Give him something to eat. Let something to eat be given (to) him. /Let him be given something to eat.
5)在下列状况下，主动句不可以转换成被动句。
1. 因为宾语的性质不需要被动句：
A. 当宾语是缺少实义的代词it时，不可以变，如：walk it, go it, fight it out
B. 当宾语为反身代词时，不可以变，如: (错) Himself was absented by him.
C. 宾语前若有主语的物主代词时，不可以变，如: (错) His finger is cut by him.
D. 当宾语是each other或one another时不可以变，如: (错) Each other is helped by us.
E. 当宾语是不定式时，极少转用于被动句。不适合说：To go is wanted by me或It is wanted by me to go.
2. 因为某些动词的性质不需要被动句, 这种动词有：become, befit, fail, last, re百度竞价推广ble, suit, suffice, wish, disappear, lack want, like, hate, possess, own, contain, have, happen to, belong to, break out, take place, set sail, shake hands with, take part in等。
3. 当某些动宾关系十分紧密不可分割时不可以变被动句。这种组合中的宾语大多表示工具、方法或结果，如：She leaned her elbows on the table. He kept silence. He took (made) a flight. The boy did not lose heart. Nydia bowed her gratitude.
4. 容易发生歧义的句子最好不需要被动句，如：The tall doctor shook his head.
6) 有的被动句不可以变成主动句，如：He was killed in war. It is said that he is ill.
