_____ of the water _____ polluted. We must try to protect our environment.
| A．Two third; are | B．Two third; is |
| C．Two thirds; are | D．Two thirds; is |
____ was your last vacation? Exciting.
| A．How | B．When |
| C．What | D．Where |
It’s too hot. We should ____ the windows ____.
| A．take, open | B．keep, opening |
| C．keep, open | D．keep, opened |
Don’t get off the bus ____ it stops.
| A．then | B．so |
| C．because | D．until |
____is “Lucky 52” shown on CCTV-2? Every week.
| A．How long | B．How often |
| C．How many times | D．How soon |
— I wonder if I can learn English well.
—________. All things are difficult before they are easy.
| A．I am afraid so | B．It serves you right |
| C．It takes time | D．It’s a piece of cake |