There is only one book of this kind left here, I wonder if you still want to buy____.
| A．it | B．one | C．some | D．any |
The experiment has_________ the possibility of the existence of any life on that planet, but it does not mean there is no life on other planets.
| A．found out | B．pointed out | C．ruled out | D．carried out |
What is the best way you can imagine ______the overuse of water in our school?
| A．reducing | B．to reduce | C．reduced | D．reduce |
—Sorry, Ann. I’m afraid that I can’t go to the magic show by David Copper Field with you.
— _____ Who knows when he will be back here again?
| A．It doesn’t matter. | B．Do as you like. |
| C．What a shame! | D．Take it easy. |
—I’d like a pen which _________ well.
—Will this one _________?
| A．is written；work | B．writes; work | C．is written; do | D．writes; do |
However，at times this balance in nature is _______ resulting in a number of possibly unforeseen effects.
| A．troubled | B．disturbed | C．confused | D．puzzled |