The first grade class gathered around the teacher for a game of "Guess the Animal." The first picture the teacher held up was of a cat. "Okay boys and girls," she said brightly, "can anyone tell me what this is?" 

"I know, I know, it's a cat!" yelled a little boy. 

"Very good Eddie. Now, who knows what this animal is called?" 

"That's a dog!" piped up the same little boy. 

"Right again. And what animal is this?" she asked, holding up a picture of a deer. 

Silence fell over the class. After a minute or two, the teacher said, "I'll give you a hint, children...it's something your mother calls your father." 

"I know, I know," screamed Eddie. "It's a Nincompoop(傻子；笨蛋)!"