Question

Cindy shut the door heavily and burst into tears. No one in the office knew _____ she was so angry.

A．where

B．whether

C．that

D．why

Answer 1

D

试题分析：考查宾语从句。knew后面是宾语从句，从句是主系表结构，不缺成分，句意：辛迪重重的关上了门大哭起来，没有人知道她为什么如此生气。根据句意可知，从句缺少“为什么”这个意思，故用why引导。故选D。