Tom dropped in to see us on his way ________ home from the theater.
| A．a | B．the | C．× | D．to |
Future will be a marvelous world of artificial ______----- robots might have their emotions and we human beings might have robots as friends．
| A．preference | B．intelligence | C．exhibition | D．communication |
As second-hand smoking is more harmful and dangerous, people want a total _____against smoking in public．
| A．ban | B．brake | C．breakthrough | D．boundary |
-- I didn't realize how popular the restaurant was until I made a reservation the other day.
-- I beg your pardon, but when __________?
| A．was you realized it | B．it was that you realized it |
| C．you realized it | D．was it that you realized it |
It_____ have been Tom that parked the car here, as he is the only one with a car.
| A．may | B．must | C．can | D．should |
-- Do you think it's a good idea to make friends with your students?
-- ______, I do. I think it's a great idea.
| A．Really | B．Obviously | C．Actually | D．Generally |