Susan won't arrive at the airport on time _____ she hurries up.
| A．once | B．if |
| C．or | D．unless |
Two fifths of the rice in our city________from Heilongjiang and Jilin．
| A．is |
| B．are |
| C．am |
| D．be |
There are________students in our school．
| A．three thousands |
| B．three thousand |
| C．three thousand of |
| D．three thousands of |
They spend two hours________TV every day．
| A．to watch |
| B．watch |
| C．to watching |
| D．watching |
They wonder when________next week．
| A．to start |
| B．start |
| C．to starting |
| D．starting |
She often encourages me________up smoking．
| A．to give |
| B．give |
| C．to giving |
| D．giving |