北师大版高中英语选修6 Unit18 Lesson2：I think it's really great, don't you? 中 “don't you?”是否正确？

章振邦《新编英语语法教程》：

    当陈述部分是一个带有that-分句作宾语的主从结构时，附加疑问部分一般应与主句的主语和谓语动词保持对应关系。但是，当陈述部分的主句是I suppose, I think, I believe等结构时，附加疑问部分则往往与that-分句中的主语和谓语动词保持对应关系。

I suppose (that) he's serious, isn't he?

I don't think (that) she cares, does she?

所以, 课本中这个句子的附加疑问部分应该用“isn't it?”更加恰当。如下面高考试题：

1. I don't suppose anyone will volunteer, ______？

Ａ. do I    B. don't I     C. will they    D. won't they  （上海高考，01-30）

答案：C

2. Mrs Black doesn't believe her son is able to design a digital camera, ______？

Ａ. is he    B. isn't he    C. doesn't she   D. does she  （上海高考，02-28）

答案：D