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    Some unwelcome visitors from North America have been turning up in the waters off the coast of Great Britain.

    North American lobsters (龙虾) have been found in the North Sea (between Great Britain and Northwest Europe), far from their own habitat. The lobsters usually live along the eastern coast of Canada and the United States.

    It is impossible that the lobsters could have made the 5,600-kilometre journey on their own. They were probably brought to Britain and then got away from containers. Some of the lobsters that were caught had elastic bands (松紧带) holding their legs shut, like lobsters that are kept in containers in stores or restaurants.

    Many may have been “set free” from some ships passing through the area. Sometimes passengers order a live lobster from a tank in the dining room and then ask the waiter to throw it overboard instead of cooking it.

    According to official records, 26 North American lobsters have been caught in waters off Great Britain since 1988. However, it is believed many more have been found but not reported.

    It is against the law to let North American lobsters come into British waters. If they settle down in European waters, it would be bad for the local lobsters. The two live in the same place and eat the same food. But North American lobsters are larger, stronger and more aggressive (好斗的) than European lobsters, and they produce young more quickly.

    As a result, they could take food and space away from the local lobsters, and from other types of shellfish that live in the same area. These lobsters may also carry diseases that could harm the local lobsters.

If you receive an e-mail that looks something like this:

    ARE YOU GOING TO CLASS TODAY? How does reading this message make you feel? Why did the sender use all capital letters(大写字母)? Was he or she angry, or did that person just forget to turn off the 'Cap Lock' on the computer? The fact is, this e-mail is usually the way that people shout online. Knowing when and when not to use capital letters is just one example of online etiquette(礼仪) —often called 'netiquette'. Virginia Shea's book, Netiquette, lists a basic set of dos and don'ts for communicating suitably with others on the Internet. Following are some of her suggestions.

    First, always remember that you are sending messages to a real person, not just to a computer. Don't type anything that you wouldn't say to someone's face. Also, remember that the person who receives your message cannot hear the tone of your voice, or see the expression on your face, so make sure your meaning is clear.

    Don't do anything online that you wouldn't do in real life. Don't take anything without paying for it, unless it's free. Don't use information that someone else has written, and say it's yours. Don't read other people's e-mail—you wouldn't open your next-door neighbor's mailbox and open their mail, right? Do share your knowledge of the Internet with others. It's a big place with lots of information, and there are many new things to discover.

    Remember that people judge(判断) you by your words as well as your actions, so try to write well. Good writing skills, as well as correct grammar and spelling, matter(有关系). Send polite, well-written e-mail messages to others. If you're uncertain about how to spell a word or which phrases to use, look it up. There are lots of helpful books and websites.

    It's okay to show your ideas online in forums(论坛) like chat room or message boards, but don't start arguments with people. 'Flame wars' in online discussions can be interesting to read, but are often unfair to other members of the group. Express your opinions, but remember that fighting online or offline is just not suitable.

    When you're online, just as in 'real' life, try to respect(尊重) other people's space, privacy and feelings. Remember, you are not the only one travelling on this highway!