6.
课文大变脸(语法填空)
We are often told that it's important to get enough sleep.
Researchers have found that it may be healthier to sleep (two) a
day. Even a ten-minute nap at noon can allow us (work) better in
the afternoon. Not getting enough sleep has serious (effect) on
our brain's ability to work. If you work without sleep, you might have problems
your memory or your concentration. In order to concentrate at
school or perform well in tests, we really need to get a good night's sleep.
Some people have trouble (sleep), especially if they are nervous
or (stress) about something. Sleep experts say that we had
better not try too hard to get to sleep, and certainly not to keep looking at
the time. (have) good sleeping habits, it's better to sleep at
regular times, and to sleep in a dark and quiet environment. amount
of sleep we need is different from person to person, the average
seems to be just under eight hours. If we feel tired in the daytime, it means
we need to get (much) sleep.