People in China used to keep records by putting a number of stones together, ? A
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People in China used to keep records by putting a number of stones together, ___?
A. usedn’t they to B. did they C. used to they D.didn’t they
试题答案
D
解析:
反意问句中陈述部分谓语是used to ,是过去式，所以简短问句中要用didn't (they)。