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Travel is fun and exciting, but it's not if you get sick．You may think,“Not me, I won't get sick on my vacation．”But for many people, that is what happens．
A vacation is supposed to be a time for relaxing．But very often it is not．“What can I do when I am a tourist?”This is what we should often think about．Usually there are so many places to visit：museums, shops, parks and churches．You may spend most days walking around these places．This can be very tiring．Your feet may hurt．And you may have a terrible headache after a few hours．If this is what you feel, you should take a rest．Don't ask your body to do too much．A tired body means a weak body．And a weak body can make you get sick easily．Just sit down for a few hours in a nice spot．In good weather, look for a quiet park bench．Or you can rest at a café．You can learn a lot by watching people when you have a rest．
Sleep is also important．If you want to stay healthy you need enough sleep．You may have trouble sleeping at night when you travel．Your hotel room may be noisy, or the bed may be uncomfortable．If that is true, don't be afraid to change rooms or hotels．You may not get enough sleep for another reason．You may want to stay out late at night．In many cities the night life can be very exciting．Then you should plan to sleep for an hour during the day．That extra hour can make a big difference．
Finally, if you want to stay healthy, you must eat well．That means eating the right kinds of foods．Your body needs fresh fruit and vegetables, and some meat, milk or cheese．When you are in a new country you may want to try new foods but you need to be careful about how much you eat．Lots of rich food is not very good for you．
e are only a few places of interest in London.