题目
Science assures that highly evolved being __________ exist on the stars and planets around if life is common in the universe.A. shouldB. wouldC. mustD. could
Science assures that highly evolved being __________ exist on the stars and planets around if life is common in the universe.
A. should
B. would
C. must
D. could
题目解答
答案
C. must
解析
本题考查情态动词的使用。根据句意，科学确信，如果宇宙中生命普遍存在，那么恒星和行星上一定存在高度进化的生物。这里的情态动词需要表达一种确定性，因此选择must（一定）。