问题
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
D
explain/ announce等后面的结构是～ sth. to sb.或～ to sb. sth.，to 不可省略。