懂英语的人进！

Complete each sentence with a suitable preposition and whom or which

1.The keys ____ _____ he opeans the doors have been lost.

2.A change ____ ____ no new substance is formed is a physical change.

3.There stand some chairs ,two ____ ____ are well shaped.

4.The persons ____ ____ I have been working are honest.

5.September 10 is Teacher's Day ,____ ____ teachers usually hold a celebration.

6.She has written another book on engineering, the name ____ ____ I have forgotten.

7.The patient ____ Dr.Black operated ____  to weeks ago has recovered.

8.This telephone has a small screen _____ _____the speakers are able to see each other.

9.The company has more than 30 offices,all ____ ____ are connected to a single computer.

10.Rose, ____ ____ I went to the concert ,enjoyed it very much.

1,by which

2,by which

of which

with whom

on which

of which

whom on

by which

of whom

with whom

1，with which

2，in which

3，of which

4，with whom

5，on which

6，about which

7，whom on

8，through which 或者 by which

9，of which

10，with whom