A boss has to interview four girls for a secretary's position.

He thought of a question and asked each one of them:

Boss: "A woman normally has two mouths, What's the difference between the two?"

The first one answered: One can talk but the other can't.

Second answered: one is vertical and the other is horizontal.

Third answered: one is hairy, the other isn't.

The last one answered: One is for my use and the other is for my boss.

Boss: You're silected.