A construction worker on the 3rd floor of a building needs a handsaw so he sees another man on the 1st floor. He yells down to him, but he can't hear, so he does sign language. He points at his eye meaning "I", points at his knee meaning "need", and moves his hand back and forth in a handsaw motion.
The man on the 1st floor nods his head, pulls down his pants, and starts masturbating.
The man on the 3rd floor gets so angry he runs down to the 1st floor and says, "What the hell is wrong with you dumbass? I said I need handsaw!!"
The other guy says, "I knew that, I was just trying to tell you I'm coming."