问题
单项选择题
It is natural for young people to be critical of their parents ______ .
A．at a time
B．between time
C．at times
D．at the time
答案
参考答案：C
解析：at times“有时”；at a time“一次；每次”；at the time of“在……时”；不说between time，但说between times“偶尔，间或”。