_______both sides accept the agreement __________ a lasting peace be established in this region.
A.Only if; will B.If only; would
C.Should; will D.Unless; would
This car is important to our family. We would repair it at our expense _______ it break down within the first year.
A.could B.would
C.might D.should
It may be necessary to stop______in the learning process and go back to the difficult points in the lessons.
A.at intervals B.at random
C.at ease D.at length
The natural environment should be protected because of the important role _______ plays in human survival and development.
A. which B. the one
C. it D. that
---Was the proposal passed at yesterday’s meeting?
---Yes, but some members of the committee expressed__________.
A. association B. reservation
C. authority D. corporation
Tom’s comments on this issue are confusing because they appear to ______the remarks on the same issue made earlier by him.
A. violate B. induce C. clarify D. contradict