----Dad, can I go out to play basketball now ?
----- Sorry, you can’t ______you haven’t finished your homework.
| A．before | B．until | C．as | D．unless |
We work together to achieve our common purpose：_________world that is safer, cleaner and healthier than one we found．
| A．the；the | B．a；不填 | C．a；the | D．the；不填 |
_________ the wind and the sun, the color on the board gradually ran.
| A．Being exposed to | B．Having exposed | C．Exposing | D．Exposed to |
It is proposed that another meeting _______ to discuss how to give more support to the underdeveloped area.
| A．be held | B．have been held | C．was held | D．will be held |
_________ I picked up the receiver, I realized that someone had dialed the wrong number.
| A．The moment | B．A moment ago | C．After a minute | D．Minute after |
Snow is rare in this area. You can hardly see any snow, ________ it is winter.
| A．ever since | B．now that |
| C．even though | D．even so |