Tell them they can't make racist jokes.
A: You lift their kilts, and whichever one has a Quarter Pounder is a McDonald!!
Because if it were invented anywhere else, it'd be called a teethbrush.
A firecracker.
A: She said they were pretty good but they might offend some Puerto Ricans.
alt) Make a joke about them, and then they'll get real offended.
With a look over the shoulder.
Looks over left shoulder* *Looks over right shoulder*