—Who is the girl standing over there?—Well, if you ________ know, her name is Mabel.
___ in thought, he almost ran into the car in front of him.
The boy wanted to ride his bicycle in the streetm but his mother told him___.
We agreeed ___ here but so far she hasn't turned up yet.
When I handed the report to John, he said that George was the person ___.
Paul doesn't have to be made ___. He always works hard.