问题
选择题
In the meeting, the professor expressed his thanks for the aid he _________ from his students.
A．received
B．was received
C．have received
D．had received
答案
答案：D
题目分析:考查动词时态。根据语境可知获得帮助是发生在动词expressed之前，表示过去的过去，所以用过去完成时，故答案选D。句意：在会议上，教授表达了他对学生们帮助的感激。