More and more people have realized that we won’t have cleaner water to drink unless something _______soon.
| A．is done | B．was done | C．will be done | D．to be done |
_____ the environment is important for human beings.
| A．Take care of | B．Taking care of | C．Took care of | D．Take the care of |
I can’t stand _____ for you so long.
| A．to wait | B．waiting | C．waits | D．waited |
—Is the bag beautiful?
—Yes, at _____ it’s _____ the one you bought for me.
| A．last; as bad as | B．least; no better than |
| C．last; not better | D．least; no worse than |
Our teacher told us that light _____ much faster than sound.
| A．traveled | B．travels | C．is traveling | D．was traveling |
In our class _____ of the students _____boys.
| A．third fifths; is | B．third fifth; are | C．three fifth; is | D．three fifths; are |