There used to be lots of old city walls in Beijing.反意疑问句如何用?

题目

There used to be lots of old city walls in Beijing.反意疑问句如何用?
There used to be lots of old city walls in Beijing的反意问句,是用"didn't there" 还是用wasn't there?理由是什么?

答案

如果说成wasn't there used to be lots of old city walls in Beijing?明显是不对的,虽然这个句子是there be句型,只是用use表示了这个句子的过去时态,但是use在其中也是个实意动词,一个句子中怎么能出现两个动词呢?所以应该用didn't.