If you go there by ____train ,you can have quite a comfortable journey ,but make sure you get ___fast one.

A．/; /              B．/; a              C．the; a            D．the ; /

 We are so sorry for that．We'll try to determine exactly _________ went wrong that evening．

A．where            B．what             C．which            D．how

With just four years _______, the Brazil Olympic organizers have promised to deliver an equally inspirational ceremony.

A．gone             B．to go             C．going             D．go

Although the causes of cancer_____, we do not yet have any practical way to prevent it.

A．are being uncovered                    B．have been uncovering

C．are uncovering                         D．have uncovered

 His idea was such a good one ______ we all agreed to use it.

A．as               B．that              C．so               D．but

What is even more important is______ the earth cooled down, water began to appear on its surface.

A．that              B．that as            C．which            D．which as

—I drove to Zhuhai for the air show last week.

—Is that ________ you had a few days off ?

A．where            B．when             C．what             D．why

---- Have you heard that Tom, as well as his parents, _____ moved to Beijing?

---- Really? No _____ I haven’t seen him for a long time.

A．have; doubt                           B．has; wonder

C．have; wonder                          D．has; choice

— Is it good to look up every new word when I come across it in reading?

—No，you _____，because you are likely to guess the meaning from the context,

A．don't have to       B．shouldn't          C．can't             D．mustn't

--Can I smoke here?

--Sorry, we don’t allow __________ here.

A．people smoke      B．to smoke          C．people smoking     D．smoking