英语作业（猜谜语）

题目

英语作业（猜谜语）
It is not in a house .
It is not outside a house.
It is part of a house.
what is it?
There is a duck in front of two ducks.
There is a duck between two ducks.
There is a duck behind two ducks.
How many ducks are there at least?

答案

1.wall
2.three