I am teaching an English class right now in a remedial type class. I was teaching about past progressive verb construction in which you use the being verb in the past tense plus the verb you want and add -ing to the ending. It would be a sentence like this: Bill was eating Rice Krispies.
I asked the class what “ing” was (meaning what is the equivalent in Spanish). One boy, who is not the sharpest knife in the drawer, blurted out “It’s a bank!” What was funny is that he could not understand why his answer was not correct.