tom doesnot believe that his son could afford to buy a digital camera,________为什么选does he而不选couldnot he
问题描述：
tom doesnot believe that his son could afford to buy a digital camera,________
为什么选does he而不选couldnot he
答
这是反义疑问句，前面是does not，所以后面要用does。
答
这个是 看前面的主句的 tom doesnot believe
前面是does not,所以后面要用does
当主语是第一人称的时候 与believe 连用 ,这样的看后面的从句
比如 i believe that his son could afford to buy a digital camera