语法是英语学习的基础，也是的基础，掌握好英语语法无论是对还是以后的英语学习都是有很大帮助的。下面小编为大家整理了常考知识讲解，一起来学习一下吧!
　　英语常考知识点讲解：被动语态 语态是动词的一种形式，它用来表示句中主语同谓语动词之间的关系。
　　英语有两种语态， 主动语态和被动语态， 主动语态表示主语是谓语动词动作的执行者，被动语态表示主语是谓语动词动作的承受者。
　　例如： I have repaired the radio.
　　我修好了收音机。
　　The radio has been repaired.
　　收音机被修好了。
　　The students cleaned the classroom.
　　学生们打扫了教室。
　　The classroom was cleaned by the students.
　　教室被学生们打扫了。
　　被动语态的构成： be 过去分词 A building was damaged by the storm.
　　暴风雨毁坏了一座建筑物。
　　Our plate was made in China.
　　我们的盘子是生产的。
　　My bike was stolen.
　　我的自行车被盗了。
　　常用的被动语态的时态变化如下，以 ask 为例： 一般 进行 完成 现在I am asked, I am being asked, I have been asked 过去I was asked,I was being asked,I had been asked 将来I shall be asked, I shall have been asked 过去将来I shall be asked 被动语态的疑问句是把助动词提前到句首。
　　Has your TV set been repaired?
　　你的电视机修了吗?
　　Was the kite broken?
　　风筝破了吗?
　　Has the work been done?
　　工作结束了吗? 被动语态的否定式是在助动词后面加 not.
　　The letter has not been sent out.
　　信还没有发出去。
　　The little boy has not been found out.
　　小孩还没有找到。
　　The cap has not been mended yet.
　　帽子还没有补好。
　　Their money has not been sent to them.
　　他们的钱还没有送到他们手中。