Having been ill in bed for nearly a month, he had a hard time ________ the exam.

Having been ill in bed for nearly a month, he had a hard time ________ the exam.

A.pass

B.to pass

C.passed

D.passing

答案及解析： D

解析：

have a hard time/difficulty/trouble...(in) doing sth．做某事很艰难、困难或有麻烦。