we are in（beijing)（对划线部分提问）

题目

we are in（beijing)（对划线部分提问）
——
where are your brothers?
——（ )
A:He is at home
B:He is in his room
C:Yes,they are
D:I don't know
There( )a computer on the desk.
A:are B:have C:has D:is
( ) there water in the cup?
A:IS B:ARE C:HAS D:HAVE
What's under the desk?
----________________

答案

Where are you in?
D因为问题是复数,而AB是单数,C不合题意.
D单数用is
A不可数名词用is
最后一题不知什么意思