Tommy was busy doing his homework. As his mother approached she heard:

"One and one, the son-of-a-bitch is two."

"Two and two, the son-of-a-bitch is four."

"Three and three... "

His mother interrupted, asking where he had learned this way of doing math.

Tommy remarked that his teacher Ms Smith taught him.

His mother was rather upset and told him to stop the homework.

The next day she stormed into s classroom and confronted Ms Smith. Tommy's mother told Ms Smith about Tommy's different way of doing math, and his claims that Ms Smith taught it that way to the class.

The teacher was flabbergasted. She said that she couldn't understand why Tommy had said what he did.

Then suddenly, Ms Smith exclaimed, "Oh, I know, here in school we say, one and one, the sum-of-which is two."