The room whose window faces south is mine.=The room of which the window faces south is mine.
The whole city, 75% of whose factories and buildings were gone, lay in ruins.
Our company has 2000 workers, of whom two thirds/ two thirds of whom are women.
Those who were trapped under the ruins finally got rescued.
The earthquake that you were talking about sounded frightening/shocking.=The earthquake about which you were talking sounded frightening.
My family, all of whom are music lovers, are going to the movie tonight.
The building which we are looking at used to be a hospital.
John once talked to his mom about the people and cities that he had visited abroad.
He is one of the tourists who have been to London.
He is the only one of the visitors that/who has been to London.
Is this the school that you visited last Sunday?
Is this school the one that you visited last Sunday?
It is in this place that he once lived.
It is the place where he once lived.
He has two sons, either of whom looks like him.
He has two sons, and either of them looks like him.
This is a book whose cover is blue.=This is a book,of which the cover is blue=This is a book,the cover of which is blue.
18. 他不说令她生气的话。He said nothing that made her angry.