The good thing about children is that they ________ very easily to new environments．

A．adapt

B．appeal

C．attach

D．apply

Titan is believed to be the only body in ________ solar system other than the Earth with liquid on ________ surface．

A．the; /

B．/; the

C．/; /

D．the; the

We ________ last night, but we went to the concert instead．

A．must have studied

B．might study

C．should have studied

D．would study

________ in the queue for half an hour, the old man suddenly realized he had left the cheque in the car．

A．waiting

B．Having waited

C．To have waited

D．To wait

Who do you think is the man ________ you are going to turn for help when you are ________?

A．who; in danger

B．to whom; in trouble

C．with whom; in danger

D．for whom; in trouble

He often helps his teachers and classmates, and is good at almost all his subjects．________, he is worthy of the honor of Top Students．

A．What's more

B．To our surprise

C．However

D．In general

We have made ________ a rule ________ in the office．

A．this; not to smoke

B．it; smoking

C．it; not to smoke

D．it; to not smoke

With a lot of difficult problems ________ , the newly-elected president is having a hard time．

A．settled

B．settling

C．to settle

D．being settled

I still remember ________ to the Tian'anmen Square and what I saw there．

A．to take

B．to be take

C．taking

D．being taken

More highways have been built in China, ________ it much easier for people to travel from one place to another．

A．making

B．made

C．to make

D．having made