______ we admit that there are some problems with the new system, we believe they can be solved.
| A．Until | B．While |
| C．As | D．Unless |
So serious that all the persons on board were killed.
| A．was the accident | B．did the accident | C．the accident was | D．the accident did |
. of the land in the district _____ surrounded with thick forests
A. Two fifth, is B. Two fifth, are C. Two fifths, isD Two fifths, are
. Words ______ me when I wanted to express my thanks to him for having saved my son from the burning house.
| A．left | B．discouraged | C．disappointed | D．failed |
_____ with a difficult situation, Arnold decided to ask his boss for advice.
| A．Faced | B．To face | C．Having faced | D．Facing |
— Learning a language isn't easy. It takes time.
—I agree. . There's no short cut.
| A．All roads lead to Rome | B．Rome wasn't built in a day |
| C．Practice makes perfect | D．Slow but sure wins the race |