问题
选择题
Jack described his father，who ________ a brave boy many years ago，as a strong－willed man.
A．would be
B．would have been
C．must be
D．must have been
答案
答案：D
根据语境可知，此处表示的是对过去事实的推测，所以用must have done结构。注意句中有一个非限制性定语从句将主句分隔开了。