it must be in the living room.( 改为反问疑问句 )it must be in the living room,isn't it

问题描述:

it must be in the living room.( 改为反问疑问句 )it must be in the living room,isn't it
为什么是isn't it而不是Must't it

must是程度副词
这里的动词是be 因为前面肯定所以后面是否定 isn‘t