Some researchers believe that there is no doubt______a cure for AIDS will be found.
| A．whether | B．that |
| C．what | D．which |
It was _________ cold winter night and the moon was shinning brightly across _________ night sky.
| A．不填；a | B．a; the |
| C．the; a | D．the;不填 |
If nothing _________, the oceans will turn into fish deserts.
| A．does | B．had been done |
| C．will do | D．is done |
Hurry up! Jack and Carol _________for us.
| A．wait | B．are waiting |
| C．have waited | D．will wait |
—Why didn’t you tell him about the meeting？
—He rushed out of the classroom _______ I could say a word.
| A．before | B．until | C．when | D．after |
All the listeners were surprised at what the traveler had ______in the last ten months.
| A．gone through | B．gone over |
| C．gone for | D．gone on |