How much sleep do we need We are all different. Some people need only three hours of sleep a night. (1) need ten hours of sleep a night. After age fifty, the average (平均) sleep time goes (2) to 6.5 hours a night.
Most of people have a night when they can’t sleep. About one (3) three Americans has a problem with (4) . Many of these of people (5) fall sleep.
This is not (6) problem. Many famous people (7) could not fall asleep. Some of these people had their own ideas (8) them sleep. Benjamin Franklin, the famous statesman and inventor had four (9) . He (10) from one to the other to fall asleep. King Lois XIV of France had 413 beds and hoped to fall asleep in one of them. Mark Twain, the famous American writer, had a different way. He lay on his side across the end of the bed!

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