Little Johnny Again with Cats!

You gotta love him!  Teacher: If I gave you 2 cats and another 2 cats and another 2, how many will you have?  Johnny: Seven, Sir.   Teacher: No, listen carefully...If I gave you 2 cats, and another 2 cats and another 2, how many will you have?  Johnny: Seven, Sir.   Teacher: Let me put it to you differently.If I gave you 2 apples, and another 2 apples and another 2, how many would you have?  Johnny: Six.   Teacher: Good. Now if I gave you 2 cats, and another 2 cats and another 2, how many would you have?  Johnny: Seven!!! SIR!   A very angry Teacher: Where in the hell do you get seven from?!?!?  A very angry Johnny: Because,.... I've already got a fuckin' cat!!!