The scientists recommend that studies ________ to find out what side effects the medicine might cause.
| A．be done | B．should do |
| C．will be done | D．are done |
— Jane, is this your umbrella?
—No, it’s not _____. I didn’t take one this morning.
| A．me | B． my | C．mine | D．I |
Three million _______ a large number. You can make it _______.
| A．are; small | B．is; smaller |
| C．is; small | D．are; smaller |
Over fifty countries _______ the AIIB(亚投行) so far.
| A．joined | B．was joining |
| C．had joined | D．have joined |
—Excuse me, madam. Could you please tell me _________ the bus arrives?
—Sure. At 9:00.
| A．where | B．when | C．why | D．how |
We stopped _________, but there was not any sound.
| A．to listen | B．listens |
| C．listen | D．listening |