Are caterpillars good to eat?
Johnny: Daddy, are caterpillars good to eat?

Father: Have I not told you never to mention such things during meals!

Mother: Why did you say that, Junior? Why did you ask the question?

Johnny: It's because I saw one on daddy's lettuce, but now it's gone.

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.