由that, which, who和whom引導的定語從句：
1.關系代詞that引導的定語從句。that在從句中作主語或賓語，可以指人，也可以指物。
如：A plane is a machinethatcan fly. (作主語，指物)
That’s is the best hotelthatI know. (作賓語，指物)
Who is the manthatis reading a book over there? (作主語，指人)
The girlthatwe saw yesterday is Jim’s sister. (作賓語，指人)
2.關系代詞which引導的定語從句。which在從句中作主語或賓語，只可以指物。
如：They planted some treeswhichdidn’t need much water. (作主語，指物)
The fishwhichwe bought this morning were not fresh. (作賓語，指物)
3.關系代詞who和whom引導的定語從句。who和whom只可以指人，分別在從句中作主語或賓語，口語中通常用who代替whom。
如：The boywhobroke the window is called Tom. (作主語，指人)
The person towhomyou talked just now is Mr Smith. (作賓語，指人)
賓語從句
用作賓語的從句叫做賓語從句。
引導賓語從句的詞有：連詞that, whether, if；連接代詞who, whose, what, which；連接副詞when, where, how, why等。
如：I doubtwhetherhe will succeed.
I wonderwhathe’s writing to me about.
I’ll tell youwhyI asked you to come.
注意：
1.賓語從句既可跟在及物動詞后面，也可跟在介詞后，還可跟在形容詞后。
如：I don’t knowwho all the people are.
Please find outwhen the ship sails for New York.
He was afraidthat the other kids would laugh at him.
2.當賓語從句后有賓語補足語時，則需要用it做形式賓語，而將賓語從句后置。
如：I finditstrangewhat she said at the meeting.
We have madeitclearthat we will learn to deal with various difficult problems.
賓語從句例句詳解
1. that引導
We believe that he is honest.我們相信他是誠實的。
The doctor insists that I give up smoking醫生堅持要我戒煙。
I suggest that we should go tomorrow.我建議我們明天走。
I suggested that we should go the next day.我建議我們第二天走。
We learnt from his letter that he was in Spain.從他的信里我們了解到他在西班牙。
The seller demanded that payment should be made within five days.賣方要求5日內付款。
2. whether / if引導
I don’t know whether he’ll arrive in time.我不知道他是否能及時到。
I didn’t know whether they liked the place.我不知道他們是否喜歡這個地方。
I’ll see whether I can induce him to accept it.我要看看我是否能勸他接受。
I asked her whether she agreed.我問她是否同意。
He enquired if her parents spoke Spanish.他問她父母是否講西班牙語。
I wonder if it’s large enough.我不知道它是否夠大。
She didn’t say if he was still alive.她沒說他是否還活著。
3.連接代詞引導
I don’t know who [whom] you mean.我不知道你指誰。
Please tell me which you like.告訴我你喜歡哪一個。
I’Il do whatever I can do.我將做我所能做的事。
You can take whichever you like.你愛拿哪個就拿哪個吧。
We’ll do whatever we can to save him.我們將盡我們所能來挽救他。
Take whichever seat you like.你要坐哪個座就坐哪個座位。
Give it to whoever you like.你把它愛給誰就給誰。
You don’t know what you are talking about.你在說什么，你自己也不知道。
Tomorrow at this time we’ll know who is elected.明天這時候我們就會知道誰當選了。
4.連接副詞引導
He asked why he had to go alone.他問他為什么必須一個人去。
You don’t know when you are lucky.你身在福中不知福。
I asked how he was getting on.我問他情況怎樣。
He knows where they live.他知道他們住哪里。
Have you found out how wide the ditch Was?你了解到那條溝有多寬嗎?
I’d like to know when they will let him out.我很想知道他們什么時候會放他出來。
We didn’t know why he had answered in that fashion.我們不明白他為什么這樣回答。