—This wall of air is an effective answer
题型:选择题
问题:
—This wall of air is an effective answer to the problem and it ________ work.
—But it is a question to put such a wall of air around the statue. [ ]
A. may
B. must
C. should
D. could
—This wall of air is an effective answer to the problem and it ________ work.
—But it is a question to put such a wall of air around the statue. [ ]
A. may
B. must
C. should
D. could