---Are the visitors all from ?— No, there are only 5 in the group.
There is ____ office on _____first floor.
A: Is the pen on the desk? B: ____.
A: Is there a computer in your class? B: ____.
A: ____ boys and girls are there in your class? B: There’re21 boys and20 girls.
—___________? —He is Andy’s father.