There must be something wrong with our machine,__there?
问题描述：
There must be something wrong with our machine,__there?
A.is B.can't
C.must d.isn't
答
1,陈述部分是there be句型时,反义疑问句要用there
2,当陈述部分含有must时,我们要具体分析must的含义,如果must意义为“一定,必须”疑问句则需要用mustn't或needn't.如果must作推测,意义为“一定是,必定”.反义疑问句要根据must后的动词选择相应的形式.
如：she must work hars atn English,mustn't she?
lily must beat home,isn't she?
在这个句子中must是用作第二种用法,所以要根据must 后面的动词be选择合适形式.所以这儿用了isn’t不懂、、、、慢慢领悟吧...这是语言习惯...