关于He can't be at home,isn't he?此句是否为反义疑问句?
关于He can't be at home,isn't he?此句是否为反义疑问句?
请问和He isn't at home,isn't he?有什么关系?为什么?也请解释一下“can't”在此处的意思.
He must be a doctor,isn't he?
You must have studied English for three years,haven't you?/ didn't you?
can 和must这些既可以表能力又可以表推测的情态动词在构成反义疑问句时是不同的,当他们表推测的时候,比如he can't be at home.这个句子的反义疑问句应该由can后面的动词决定,所以用isn't he?当can 表示能力的时候,如...he can't be at home.这个句子是表否定的吧，为什么不用is he？呢？的确前面是否定句，后面应该用肯定。eg: He must be a docter,isn't he?所以你的句子应该是He can't be at home, is he? 他一定不在家，是吗？还有，你后面的那个句子应该也是错的，应该是：He isn't at home, is he ?他不在家，是吗？You must have studied English for three years, haven't you? 这句中的must 是一定的意思，表推测。你学习英语已经有三年了，不是吗？You must have studied English for three years,didn't you?句中有明显的表示过去的时间状语 ，反义疑问句就只能用一般过去时，不可以用完成时。eg: she must have finished reading the novel last night, didn't she ? 这句里面有明显的过去时间last night,所以用didn't.你这句里面没有明显表示过去的时间，但是for +一段时间也可以与一般过去时态连用，所以也可以用didn't来构成反义疑问句，意思跟上句一样，但前面的句子是完成时态，所以最好还是用haven't you?希望你看得明白