70. The report from NHTSA
suggests that .
A.
fewer people were injured in crosswalks
B.
crosswalk safety has greatly improved
C.
much has been done to reduce traffic accidents
D.
pedestrian deaths in crosswalks remain a serious problem
E
根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。
Sleep is
something we all do. But some people need to sleep more than others. Babies
sleep most of the time. Children in school sleep about ten to twelve hours a
night. Most grown-ups sleep only seven or eight hours. 71
All parts of our
bodies have to rest after they work. Our arms need a rest after we lift heavy
things. When we run fast, our legs work hard. They get tired. We have to rest
them. Our brains work hard, too. 72 We can sit quite still and rest our
arms and legs. But our brains aren’t resting. They go right on thinking as long
as we are awake.
Our brains slow
down a bit when we sleep and dream. 73 Instead of thinking wide-awake thought,
our brains make up dreams. Some dreams are very pleasing. Some are not. Most of
the time we forget them when we wake up.
Scientists have
tried to find out what would happen if people were not allowed to sleep. They
asked some people not to go to bed. The people stayed up all night and all the
next day. They stayed up the next night, too and the day after. They played
games. But they made mistakes. They forgot things. 74 . The people grew rude
and mean. They became angry with their friends. Finally they were too tired to
stand up. The moment they sat down, they fell asleep.
Scientists found
that if people are not allowed to sleep, they act in an unusual way.
75 But we do know that we need it to stay
well.
So tonight have a
good sleep. Lie down under the covers. Shut your eyes. Let your thoughts travel
about. Soon you’ll stop thinking. You’ll be asleep.
A.
But even as we
sleep our brains are doing some work.
B.
It was hard for
their tired brains to work.
C.
When we are
awake, they help us pay attention to the world around us.
D.
No one knows
quite surely why sleep is so good for us.
E.
Good sleep helps
to improve one’s memory.
F.
But babies,
children and grown-ups ----all of us need to have our sleep.