问题
选择题
— The terrible accident is under investigation．
— Actually, quicker action _____ those workers trapped in the mine．
A．might have saved
B．must have saved
C．should have saved
D．could have saved
答案
答案：D
考查情态动词及虚拟语气。might have done 对过去可能性的推测，must have done对过去肯定的推测，should have done本应该做某事，实际上没有做，could have done本可以做某事，实际上没做，根据句意更快的行动本可以救那些困在矿中的工人的。所以选D。