A teacher says to Little Johnny “If I gave you two cats and another two cats and another two, how many cats would you have?”
Johnny says “Seven.”
Teacher says “No, listen carefully. If I gave you two cats, and another two cats and another two, how many would you have?”
Johnny again says “Seven.”
Teacher says “Let me put it to you differently. If I gave you two apples and another two apples and another two, how many would you have?”
Johnny says “Six.”
Teacher says “Good. Now if I gave you two cats, and another two cats and another two, how many would you have?”
Johnny says “Seven!!”
Teacher says “Johnny! Why do you keep saying seven?!”
Johnny says “Because I’VE ALREADY GOT A FUCKING CAT.”