— What do you think of the book?— Oh, excellent. It is worth ________ a second time.
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.