语法：主动形式表示被动意义

1)wash, clean, cook, iron, look, cut, sell, read, wear, feel, draw, write, sell, drive…
The book sells well.　这本书销路好。
This knife cuts easily.　这刀子很好用。

2)blame, let(出租), remain, keep, rent, build
I was to blame for the accident.
Much work remains.

3) 在need, require, want, worth (形容词), deserve后的动名词必须用主动形式。
The door needs repairing.= The door needs to be repaired.
This room needs cleaning. 这房间应该打扫一下。
This book is worth reading.　这本书值得一读。

4) 特殊结构：make sb. heard / understood (使别人能听见/理解自己)，have sth. done ( 要某人做某事)。