The number of people who ____English as a foreign language __more than 750 million.
| A．learns; is | B．learn; are | C．learns; are | D．learn; is |
"We can’t go out in this weather," said Bob, ________ out of the window.
| A．looking | B．to look | C．looked | D．having looked |
Scientists are convinced _______the positive effect of laughter ______ physical and mental health.
| A．of ; at | B．by ; in | C．of ; on | D．on ; at |
Many of them turned a deaf ear to his advice, ________ they knew it to be valuable.
| A．as if | B．now that | C．even though | D．so that |
It is so difficult a question_______ none of the kids could work it out.
| A．as | B．that | C．which | D．X |
Kunming is called“Spring City”, but it _____ snow in winter.
| A．shall | B．can | C．must | D．might |