1 . —I’m not sure ________ you eat vegetables every day.     
—I know ________ they are good for our health, so I eat them every day.

A．if; that

B．that; if

C．that; that

D．if; if

2 . Jim hasn’t decided ________ to go home by bus or by train.

A．if

B．that

C．how

D．whether

3 . —I wonder ________.
—Well, I think the Lake Park is a good choice.

A．what I shall sell at my street stall	B．whom I could open a street stall with
C．if I can open a street stall after work	D．which is the best place for a street stall

4 . —Could you tell me ________?
—Certainly.

A．how long you will leave	B．if the air is badly polluted
C．whether you had got ready for the exam	D．what’s the story about

5 . —The match is so exciting. The opposite team is really strong.
—Yes, I doubt ________ our team will win or not.

A．if

B．that

C．whether

D．why

6 . —Do you know ________ the Smiths left Shanghai?
—I’m not sure about the date. I only remember it was a Sunday.

A．if

B．why

C．how

D．when

7 . It’s amazing! I can’t believe ________ you could make it to the top in such a short time!

A．which

B．what

C．that

D．if

8 . —Do you know ________ The Betl and Road Forum(“一带一路”高峰论坛) began?
—On May 14^th, 2017.

A．that

B．when

C．if

D．where

9 . Having worked for a whole day, I was so tired ________ I fell asleep.

A．because

B．if

C．although

D．that

10 . Do you know ________ he did not turn off the light?

A．what

B．how

C．if

D．why