There are over 58,000 rocky objects in _____ space, about 900 of which could fall down onto _____ earth.
| A．the; the |
| B．/; the |
| C．the; / |
| D．a; the |
--Mom, may I play computer games just for a while?
--______! Dad is writing his paper.
| A．Help yourself |
| B．It's up to you |
| C．Go ahead |
| D．Behave yourself |
It took ______ building supplies to construct these energy saving houses. It took brains, too.
| A．other than | B．more than |
| C．rather than | D．less than |
Though it is 20 years ______ we last met, I still remember the scene______ we got separated on a snowy day.
| A．before; where | B．before; which |
| C．since; when | D．since; where |
She is very dear to us. We have been prepared to do ______it takes to save her life.
| A．whichever | B．however |
| C．whatever | D．whoever |
My grandfather is as ______ as a young man and hates sitting around doing nothing all day.
| A．enthusiastic | B．energetic |
| C．talkative | D．sensitive |