Charlie was about to climb into bed when he found there was a light on in his garden shed(棚). Then he noticed some people who were busy stealing his things.
    He call the police right away. The policeman asked, “Are there any intruders(闯入者)in your house?” Charlie replied “no” and explained what was happening.
    The policeman said, “All patrol cars(巡逻车) have gone out, and a policeman will go to your house when one is free.”
    Charlie hung up, waited 30 seconds, and then called the police again. “Hello, I just called a short while ago because there were people stealing things from my shed. I want to let you know that they're not a problem anymore because I've just shot every one of them.”
    Charlie then hung up the phone. In five minutes, three patrol cars, nearly twenty policeman and an ambulance arrived at his house. Of course, the police caught the thieves.
    One policeman said, “I thought you said that you shot every one of them!”
    Charlie replied, “I thought you said there were no patrol cars free!”