1）can/could+be+動(dòng)詞過去分詞，表示“可以被……”“可能被……”“應(yīng)該被……”“必須被……”等

除了can/could，還可以用情態(tài)動(dòng)詞may/might;must/have to;should/ought to;had better/would rather;use to/would等

需要注意：need+doing直接表示“需要被……”

2）和情態(tài)動(dòng)詞結(jié)合的形式：

The food could be taken away.

食品可以被帶走

The food might be taken away.

食品可能被帶走

The food must be taken away.

食品必須被帶走

The food should be taken away.

食品應(yīng)該被帶走

The food needs taking away.

食品需要被帶走

The food had better be taken away.

食品最好被帶走

Books used to be returned in two days.

書本過去常常在2天之內(nèi)被還回去

每日一句：Doubt is the key to knowledge.懷疑是知識(shí)的鑰匙