Bilingual Parrot

This guy goes to a pet shop. There he sees a parrot with a red string
tied to its left leg and a green string tied to it's right leg. He asks
the owner the significance of the strings.

"Well, this is a highly trained parrot. If you pull the red string
he speaks French; if you pull the green string he speaks German,"
replies the shop keeper.

"And what happens if I pull both the strings at the same time?" the
shopper asks.

"I fall off my perch!" squawks the parrot.