问题
单项选择题
She was just about to explain ______ she hadn't passed her maths test chiefly out of carelessness ______ her uncle came.
A. her mother when
B. to her mother
why that
C. her mother
that when
D. to her mother
that when
答案
参考答案：D
解析： explain/announce等后面的结构是～sth to sb或～to sb sth，to不可省略，第二空when引导时间状语从句。故选D。