A man phones a mental hospital and asks the receptionist...
A man phones a mental hospital and asks the receptionist if there is anybody in room 27. She goes and checks, and comesback to the phone, telling him No, the room is empty. "Good," says the man. "That means I must have really escaped."

2 Mexicans
A Border Patrol agent is on duty. He spots two Mexicans and runs them down. They show him their papers (he thinks they are phony).

He tells them, "O.K. I have a test for you. I want you to use the words 'cheese' and 'liver' in a sentence."

So, the first guy says, "I made a liver and cheese sandwich for lunch."

The agent says, "That was good, you can go. What about you?" he asks the second guy.

He says, "Liver alone. Cheese mine."