问题
选择题
“Why didn’t she come to the meeting yesterday?” “I’m not so sure. She ______ ill.”
A．should be
B．should have been
C．must be
D．might have been
答案
答案：D
从时间上看，由于是昨天没来开会，所以推测他生病也应指昨天，故排除A和C。从语境上看，既然上文说 I’m not so sure，那么说明说话者对自己的推测没有很大把握，故选D。