这是一个宾语从句。

This is an object clause.

宾语从句:介词的宾语.

I am interested in what she is doing.

宾语从句:短语动词.

Please go and find out when the train will arrive.

我知道这些都是宾语从句”。

I know that these are objective sentences.

宾语从句，我忘了我什么时候住在那里

I forgot when i lived there.

宾语从句他想知道我们是否使用电子字典

He wants to know whether we use an e-dictionary

我被选参加会议，感到光荣。（宾语从句）

I regard it as an honor that I an chosen to attend the meeting.

请告诉我你是否想加入我们。引导的从句可被看成是宾语从句，if表示是否

Whether. Please let me know if you want to join us.

你知道他们在找谁吗?(宾语从句，陈述语序。

Do you know whom they are looking for?

我不知道他为什么还没来。(宾语从句，陈述语序。

I don’t know why he hasn’t come yet.