被动语态通常为十种时态的被动形式， 被动语态由be＋过去分词构成，be随时态的变化而变化。
以put为例，各种时态的被动语态形式为
例：
The meeting is to be put off till Friday.
If it rained tomorrow， the sports meet would be put off.
The beauty of that light， like love， is not to be touched， not to be put into a word.
那光的美，就像爱，无法被触及，无法被诉诸语言。
要是明天下雨，运动会就推迟
be put被动形式
被动语态由be+过去分词构成，put的过去分词和原型一样，还是put，所以put的被动是be put。
He put the bag into the desk.主动语态改为被动语态
The bag was put into the desk by him解析：He put the bag into the desk.此句中的put 是过去式，一般过去时的被动语态结构：主语+ was/ were + 过去分词...
