1 . It was then ________ I realised mom’s seat was empty!

A．who

B．where

C．that

D．which

2 . It is along these waterways          rainwater moves down the mountains and into the terraces.

A．what

B．which

C．that

D．where

3 . Is it in this room ______ the great writer once lived ______ he finished his last works?

A．that; that

B．where; that

C．that; where

D．that; which

4 . It is the production of food, not its transport, ________ uses most of the energy and produces most of the greenhouse gases.

A．which

B．what

C．that

D．where

5 . It was in the small house _______ was built with stones by his father _______ he spent his childhood.

A．which; that

B．that; which

C．where; that

D．that; where

6 . It is the production of food, not its transport, ________uses most of the energy and produces most of the greenhouse gases.

A．that

B．which

C．what

D．when

7 . It is children’s health__________ parents are concerned about.

A．why

B．when

C．that

D．which

8 . You are waiting at the wrong place. It is at the hotel________the coach picks up tourists.

A．which

B．that

C．what

D．why

9 . In fact, it was in the United States ________ Mike met his wife and married her.

A．when

B．that

C．where

D．which

10 . When was ________ you met your best friend at the street?

A．it that

B．it

C．the time

D．there