问题
选择题
I don’t understand ______ such a silly question in class yesterday.
A．why did John ask
B．why John asked
C．why is John asking
D．why John asks
答案
答案：B
考查宾语从句。根据宾语从句的陈述语序，排除A、C，再根据宾语从句的时态规律，可见主句是一般现在时understand，从句中出现yesterday，则从句用一般过去时。
根据所给的汉语内容，用英语完成下列句子。（每空限一词）