this is( )room.
问题描述：
this is( )room.
A.Tom and Mary's B.Tom's and Mary's C.Tom's and Mary D.Tom and Mary
答
A
首先这里要用名词所有格,由于后面的room为单数形式,说明是共同拥有的关系,此时应该在最后一个名词后加‘s.