Border Patrol Test

A Border Patrol agent is on duty. He spots two Mexicans and stops them. They show him their papers, but he thinks they are phony.

He tells them, "Okay, I have a test for you. I want you to use the words liver and cheese 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."