Only in this way,can you learn English well.

Only after being asked three times did he come to the meeting.

如果句子为主从复合句，则主句倒装，从句不倒装

Only when he is seriously ill,does he ever stay in bed.

动词的几种语态

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.

我们的盘子是中国生产的。

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.