问题
选择题
If you feel tired and sick of fat food, that is ______ you have to go to the hospital for medical examination.
A.why
B.whether
C.when
D.what
答案
答案:C
主要测试表语从句。译文:如果你感到疲惫,而且不喜欢油腻食物,那就是你必须去医院做个检查的时候了。