—I think it's going to be a big problem.

—Yes, it could be.

—I wonder ___________  we can do about it.

A. if　　　　　　　　　　　　　　　　　　　　　　　　　　　　 B. how

C. what　　　　　　　　　　　　　　　　　　　　　　　　    D. that

The fifth generation computers, with artificial intelligence, _______and perfected now.

A. developed　　　　　　  B.are being developed

C.will have been developed　　   D.have developed

They _______ the train until it disappeared in the distance.

A. saw　　　　　　　　  B.watched　　　　　　　　    C.noticed　　　　　　   D.observed

He looked quite healthy though he was_______.

A. in seventy   B.in his seventy　　  C.at seventy　　　　   D.at the age of seventy

My name is Robert, _______most of my friends call me Bob for short.

A.then　　　　　　　　   B.instead　　　　　　　　　　  C.however　　　　　　 D.but

In the cross-lake swimming race, a boat will be _______in case of an emergency.

A. standing by　　    B.turning on　　　　　　　　  C.getting on　　　　   D.running down

All the employees except the manager __________ to work online at home.

A. encourages　　      B. encourage　　  　　  C. is encouraged　　  D. are encouraged

The new research team was led by the __________ engineer.

A. main　　  　　   B. major　　  　　  C. chief　　  　　  D. primary

You took the photos. Why didn’t you develop them __________?

A. either　　  　　　　　　 B. too　　  　　　　　　    C. as well　　  　　　　   D. instead

It’s important for us to employ a word or a phrase according to the __________ in language studies.

A. situation　　  　　　　 B. expression　　  　　  C. condition　　  　　　　　　  D. translation