Could you tell me ------?what was the matter填这个答案可以吗?是陈述语序吗?

Could you tell me what was the matter?
绝对没错,疑问词“what”做主语,是陈述语序,没错!这题是典型易错题,我经常考学生的。你只要记住就行了。
或者可理解为：这里“the matter”相当于“wrong”,具有形容词的性质,不能做主语,所以主语由疑问词"what"来充当。