核心问题
I don't suppose that he cares,
请问在这种句型里是应当用 does he，还是应当用 doesn't he 呢？
词典解答
在 think, believe, suppose, expect 等动词后面的从句中, 如果在意义上需要否定宾语从句的某个成分, 常常要将否定转移到主句中去。因此, 所提问的句子 I don't suppose... 相当于 I suppose that he does not care. 这就意味着, that 从句实质上是个否定句。按照附加疑问句的使用规则, 这里的附加疑问句只能使用肯定形式: does he? (参见 transferred negation , tag questions )