A word play

A teacher asked her students to use the word "fascinate" in a sentence. Mary said, "My family went to the New York City Zoo, and we saw all the animals. It was fascinating." The teacher said, "That was good, but I wanted the word "'fascinate.'" Sally raised her hand. She said, "My family went to the Philadelphia Zoo and saw the animals. I was fascinated." The teacher said, "Good, but I wanted the word 'fascinate.'" Little Billy raised his hand. The teacher hesitated because Billy was noted for is bad language. She finally decided there was no way he could damage the word "fascinate" so she called on him. Billy said, "My sister has a sweater with 10 buttons, but her boobs are so big she can only fasten 8."