Napoga is a 12-year-old girl in Ghana(加纳)，Africa．It is hard for her family to get clean water．Every morning，she leaves home at half past five to get clean water for her family in a village far away．It takes her six hours to get enough clean water for daily cooking and drinking．She has no time to go to school or to play with her friends．Millions of people in the world are like Napoga．They can't get enough clean water to keep healthy．
Earth Day is April 22．But on all other days，we must also remember it．The water we use is the most important natural resource(自然资源)on the earth．
Water covers 70％ of the earth's surface．But most of that is sea water．We can't use it for very many things．Fresh water covers only 1％ of the earth's surface．
You probably feel lucky that your life isn't as hard as Napoga's．But that doesn't mean you don't have to worry about water．We all face serious water problems．One of them is water pollution．All kinds of things from cars，factories，farms and homes make our rivers，lakes，and oceans dirty．Polluted water is very bad for people to drink．And dirty water is bad for fish，too．Now, 34％ of all kinds of fish are dying out．
How do cars and factories make our water dirty? First，they pollute the air．Then，when it rains，the rain water comes down and makes our drinking water dirty．Dirty rain，called acid rain(酸雨)，is also bad for plants，animals and buildings．
Scientists say that in 30 years，more than half of the people in the world won't have enough clean water．We have to learn how to save more water for ourselves and our children．Here is some advice for saving water：
●Turn off the water while you brush your teeth．You can save as much as 450 liters(升)each month．
●Leaky taps(漏水的龙头)waste a lot of water．Fix them right away!
●You can easily cut your 10-minute showers in half-and you'll be just as clean．
●When you wash dishes，don't let the water run．
●Only wash clothes when you have a lot to wash．If your washing machine isn't full，you're wasting water!
(1)
On the earth, ________．
[ ]
A．
sea water is more widely(广泛地)used than fresh water
B．
there is very little water for our living
C．
there is 71％ of fresh water
D．
we don't need to worry about water
(2)
Acid rain ________．
[ ]
A．
is only bad for living things
B．
can be produced in factories
C．
doesn't do harm(伤害)to people，but it's bad for plants，animals and buildings
D．
doesn't just do harm to human beings but to animals，plants and buildings
(3)
Which of the following wastes water?
[ ]
A．
We need ten minutes if we want a clean shower．
B．
We should put in enough clothes when we wash them in washing machines．
C．
You can keep yourself clean by having a shower for five minutes．
D．
Don't let the water run when we brush our teeth and wash dishes．
(4)
What's the main idea of the passage?
[ ]
A．
Something must be done to prevent water from being polluted．
B．
Clean water means much to human beings and living things around us．
C．
It's time to take care of the water we use．
D．
Water is the most important natural resource on the earth．
Napping(小睡)after learning something new could help improve your memory--- as long as you dream, scientists say．
They found people who dream about a new task do it better on waking than those who do not sleep or do not dream．
Volunteers were asked to learn the layout(布局，设计)of a 3D computer maze(迷宫)so they could find their way several hours later．Those allowed to take a pap and who also remembered dreaming of the task, found their way to a landmark quicker．
The researchers think the dreams are a sign that unconscious(无意识的)parts of the brain are working hard to process information about the task．．
Dr．Robert Stickgold of Harvard Medical School, said dreams may be a marker that the brain is working on the same problem at many levels．
Study tips
Co-author Dr．Erin Wamsley said the study suggests our non-conscious brain works on the things that it deem(认为)are the most important．
“Every day we are gathering lots of information and new experiences,” she said．“It would seem that our dreams are asking the question, “How do I use this information to inform(影响)my life?”
The scientists say there may be ways to use this phenomenon(现象)for improving learning and memory．For example, students might be better studying hard before bedtime, or taking a nap after a period of afternoon study．
(1)
Scientists say ________ could help improve your memory．
[ ]
A．
dream
B．
nap
C．
nap and dream
D．
nap without dream
(2)
What were volunteers asked to do?
[ ]
A．
Take a nap．
B．
Dream a task．
C．
Learn about 3D computer．
D．
Find their way out of a maze．
(3)
Which is right about dreams?
[ ]
A．
They are a sign that parts of the brain is unconscious．
B．
They can help us fall asleep and improve learning and memory．
C．
They tell us how to use this information to inform our life．
D．
They may be a marker that the brain is working on the same problem．
(4)
When is the best time for study?
[ ]
A．
Before bedtime．
B．
After bedtime．
C．
Before taking a nap．
D．
In the afternoon．
阅读理解
Did you sleep well last night?Maybe many people will answer：No．In fact, in the world about one third of the people do not have good sleep．If you say you do not have good sleep, it means：waking early and not getting back to sleep．You may get tired, worried and anxious．Your memory and ability to remember things will get worse．
Then what should you do when you have the trouble?Do not worry about it too much．Let’s see if you can help yourself．The techniques(技巧)are as follows：
First, make sure that your bedroom isn’t too cold or too hot．Keep it dark and quiet．
Second, check your lifestyle：
Do not drink tea, coffee, cola or chocolate four hours before bed．Drink less water and avoid night-time toilet visits．
Set your body clock well by getting up and going to bed at the same time every day．Avoid daytime naps．
Develop a relaxing bedtime habit．Read or listen to music, then take a warm bath．If you really can not sleep, try some bread, rice or milk．They will help you fall asleep．
Go for a daily walk．Natural light helps you regulate(调理)your body clock, so exercise outdoors if you can．
Forget the worries of the day．Write down any worries, thoughts or questions before you go to bed．With these written down, you will have less to think about and your sleep will become easier．
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