I’m sorry, I really don’t know ________ the clock．

A．to mend

B．how should I mend

C．what to mend

D．how to mend

You will be able to get good marks ________．

A．while you are doing your homework by yourself

B．if you do some revision every day

C．before you begin to study hard

D．until you follow your teacher’s advice

－Could you help me put up the signs on the wall?

－________．

A．No problem

B．I hope so

C．That’s all right

D．That’s a good idea

This story ________ tells us how Bill Gates becomes successful．

A．mostly

B．mainly

C．most

D．A and B

Could you tell me when ________?

A．does the train leave

B．will the train leave

C．the train has left

D．the train leaves

Excuse me, could you help me?I don’t know ________ exchange money．

A．how to

B．how

C．how can

D．how can I

Do you know ________?

A．what the news are

B．what is the news

C．what the news is

D．what are the news

I want to know how long ________．

A．has he been back

B．has he come back

C．he has been back

D．he has come back

I didn’t know how ________ to London?

A．would they go

B．are they going

C．they would go

D．they are going

Can you tell me ________?

A．where he is

B．where is he

C．he is where

D．what is he