问题补充:
the flight to New York will be delayed is I’m especially worried about.
A. If; what
B. Whether; that
C. When; that
D. Whether; what
答案:
A. If; what
B. Whether; that
C. When; that
(答案→)D. Whether; what
解析:考查名词性从句。句中whether引导主语从句,句首不可用if,what引导表语从句,在从句中作宾语,选D。