问题
选择题
—Where ____ Margaret have put the empty bottles?
—She ______ them away. They must be somewhere.
A．can; can’t have thrown
B．must; needn’t
C．must; must have thrown
D．can; must throw
答案
答案：A
本题考查情态动词+have done表示对过去事实的推测的用法。must have done用于肯定句中，疑问句否定句中应用can could代替must。故选A。