问题补充:
He insisted that hesuffer from heart trouble, but I didn’t think so.
A. should suffer
B. has suffered
C. suffers
D. was suffering
答案:
A. should suffer
B. has suffered
C. suffers
(答案→)D. was suffering
解析:考查时态。句意:他坚称他正患心脏病,但是我不这么认为。可知前文描述的是过去正在发生的事情,故用过去进行时态。选D。