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."

After many years of trying to find steady work...
After many years of trying to find steady work I finally got a job as a historian until I realized there was no future in it.