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Light travels at a speed which is about a million times faster than the speed of sound. You can get some idea of this difference by watching the start of a race. If you stand some distance(距离) away from the starter, you can see smoke from his gun before the sound reaches your ears.
This great speed of light produces some strange facts. Sunlight(太阳光) takes about 8 minutes to reach us. If you look at the light of the moon tonight, remember that the light rays left the moon 1.3 seconds before they reached you. The nearest star is so far away that the light that you can see from it tonight started to travel towards you four years ago at a speed of nearly 2 million km. per minute. In some cases, the light from one of tonight’s stars had started on its journey to you before you were born.
Thus, if we want to be honest, we can’t say, “The stars are shining tonight.” We have to say instead, “The stars look pretty. They were shining four years ago, but their light has only just reached the earth.”
Light speed is ______ sound speed.

A.as fast as
B.a million times slower than
C.about millions of times faster than
D.about a million times faster than

If you stand 200 meters away from a man who is firing a gun to start a race, you will find out that ______.

A.you can hear the sound before you see the smoke
B.the sound does not travel as fast as light
C.the sound will reach you before the man fires
D.sound travels about a million times faster than light

Sunlight obviously(显然的) ______ than the light of the moon.

A.has to travel a greater distance
B.moves less quickly
C.travels much more quickly
D.is less powerful

The scientific way of saying "The stars are shining tonight" should be ______.

A.the stars have been shining all the time
B.the stars seen tonight will shine four years later
C.the stars were shining long ago but seen tonight
D.the starlight seen today could be seen four years ago
科目 英语   题型 阅读理解   难度 中等
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School homework and use of electronic devices(电子仪器)are main causes, a report says. More than 60% of children and teens do not get adequatesleep, which can put their health at risk, according to a report that came out on Sunday by the Chinese Sleep Research Society. The report was from a survey at the end of last year and in January. It covered nearly 70,000 children and teens aged 6 to 17 across the Chinese mainland, Hong Kong, Macao and Taiwan.

The report found that the heavy school homework load(负荷)and the popularization of electronic devices were the two top causes for the inadequate sleep. From Monday to Thursday, 8. 4% of the group would still be busy with their homework after 11 p. m. More than 41% of children and teenagers who sleep too little use electronic devices, and children whose parents use smartphones in front of them are more probably to have less sleep. Other reasons, such as noise and light pollution, made the problem happen, the report said. The survey also showed that good sleep results in higher efficiency(效率)in study.

Gao Xuemei,vice﹣president of the society, said studies have shown that decreasing(减少)sleeping time for children and teenagers has been a global trend(全球趋势)in the past 10 years,but the problem appears to be worse in East Asia, including China, largely because of a heavier load of school homework.

"Lack(缺失)of sleep among children and teenagers is worth paying high attention to,because it can seriously affect their health and growth," she said. "Such a group should sleep at least eight hours a day," she added. "Sleep develops growth, protects the brain and improves the immune system(免疫系统)," she said. "Long﹣term lack of sleep will bring risks of diseases(疾病)and conditions such as dementia(痴呆)and cause lasting health harm."

(1)The word "adequate" in Paragraph 1 probably means "   ".

A.

enough

B.

much

C.

necessary

D.

helpful

(2)The two top causes for the inadequate sleep are   

A.

noise and the heavy school homework

B.

light pollution and the heavy school homework

C.

the heavy school homework and electronic devices

D.

Delectronic devices and noise

(3)From the passage we can learn   

A.

the more children sleep,the higher their grades are

B.

parents influence their children less if they use smartphones

C.

noise and light pollution play an important role in the sleeping problem

D.

children in East Asia may lack more sleep than those in other parts of the world

(4)Sleep helps us a lot EXCEPT   

A.

developing growth

B.

protecting the brain

C.

improving the immune system

D.

bringing risks of diseases

(5)The writer wants   by the passage.

A.

to find out the reasons for children's inadequate sleep

B.

to stop children and teenagers using electronic devices

C.

us to pay high attention to lack of sleep among children and teenagers

D.

us to cut down children and teenagers′ heavy school homework

Grand Opening of The Book Nook

Saturday, June 8:10 a.m. to 10 p.m.

You will not want to miss this celebration for the opening of a new neighborhood bookstore! Built at 2289 Main Street, The Book Nook is close to schools and many homes and businesses. Come and check out The Book Nook on Saturday!

Festivities will include:

● Free food and drinks

●Live music by local musicians

●One Book-of-the-Month Club membership giveaway

Wide Choice

The Book Nook has three floors filled with books of all kinds. If we do not have the book you are looking for, we can specially order it for you. You will have it in your hands in two days!

Book Events

The Book Nook will hold monthly book signings by different writers, giving you a chance to meet and speak with well-known writers. Do not miss the unforgettable experience of hearing famous writers read their own books aloud! We also have summer reading programs for children of all ages. These programs are a great way to meet other children and share ideas about your favorite books.

The Book-of-the-Month Club

As a member of our Book-of-the-Month Club, you can choose one new book each month. The membership fee(会员费)is $120. That is a great price for 12 books a year!

So please join us on Saturday and learn about all that The Book Nook offers. You can come anytime between 10 a.m. and 10 p.m.- the celebration lasts all day long!

1.The Book Nook is not far from .

A.

schools and many homes

B.

many homes and businesses

C.

schools, businesses and few homes

D.

schools, many homes and businesses

2.At the opening,The Book Nook will .

A.

offer free food and drinks

B.

give away free books

C.

invite children to play music

D.

provide free special orders

3.At the monthly book signings,you can .

A.

read books aloud to famous writers

B.

meet and speak with famous writers

C.

hear famous writers read your favorite books

D.

talk about your favorite books with famous writers

4.The Book Nook also has summer reading programs for .

A.

doctors

B.

police

C.

children

D.

managers

5.The price of the Book-of-the-Month Club membership is .

A.

$12 a year

B.

$120 a year

C.

$12 a month

D.

$ 120 a month

Once upon a time, there was a king. He only had one leg and one eye,but he was very smart and kind. Everyone lived a happy and healthy life because of the king. One day, the king was walking through the palace hallway and saw the paintings of his ancestors(祖先).He thought that one day his children would also walk in the same hallway and remember all the ancestors through these paintings.He wanted his children to remember him,too.So he invited many famous artists

to his palace.

All of the artists began to think about the king's physical disabilities(生理缺陷). How could his painting be made very beautiful?It was not possible.They weren't sure what his painting would be like.So one by one, they all started to politely refuse to make a painting of the king.

But suddenly one artist raised his hand and said he would make a very nice painting of the king. The king became happy hearing that. Then the artist started painting. After a long time, the painting was ready.

When the artist showed the painting, everyone was shocked. In the painting, the king was sitting on a horse, on the one﹣leg side, holding his bow (弓箭) and aiming (瞄准) something with his one eye closed. The king was very happy and gave him lots of money.

As we all know, no one is perfect. So we should try to focus on (关注) others' advantages instead of their disadvantages. Just take an optimistic view (乐观的观点) of the event. Everyone can do a good job.

(1)What did the king see in the palace hallway?   

(2)Why did the king invite artists to draw a painting of him?   

(3)Was it an easy job or a hard job to draw a painting of the king.   

(4)How did the king like the painting?   

(5)What can we learn from the artist?   

Do you think laughter can help you deal with pain? Scientists from Britain did two experiments(实验). The first was done in a lab. People wore special wristbands(腕带). Some of them were asked to watch comedies while others watched serious programs. Then the scientists tightened(勒紧)the wristbands to see how much pain the people could feel.

The other test was done at an art festival. Some people watched a comedy show and others watched a drama(戏剧). At the same time, they had to put their backs against the wall and keep their legs bent(弯曲的)just like sitting on a chair. They did this before and after the show.

Scientists found that just 15 minutes of laughter improves people's ability to stand pain by 10%.However, the serious programs and the drama didn't make a difference to pain at all.

The study found that the magic power of laughter comes from endorphins(内啡肽). These are chemicals(化学物质). They are produced by the human body. They make you feel less pain and can make people feel happier. Exercise can produce endorphins.Your muscles(肌肉)move in and out when you are laughing.Scientists believe that this makes your muscles tiring,so we start to produce endorphins.

Scientists also found that the only real and relaxing laughter works not just polite laughter.

Next time you have a headache,get together with a group of Mends,watch a funny movie and laugh.You will soon feel a lot better because laughter is the best medicine.

(1)Scientists knew how much pain the people felt by   in the first experiment.

A.

eating delicious dishes

B.

putting backs against walls

C.

tightening special wristbands

D.

sitting on comfortable seats.

(2)The other test was finished   

A.

on a chair

B.

in a lab

C.

on Sports Day

D.

at an art festival

(3)Endorphins can help human body   

A.

keep better build

B.

feel less pain

C.

get more muscles

D.

produce worse results

(4)According to the passage, we can infer that   

A.

running can produce endorphins

B.

watching TV programs can stand pain

C.

different kinds of laughter earl treat illness

D.

muscles can improve people's ability to laugh.

(5)We can probably find this passage in a   

A.

guide book

B.

movie poster

C.

travel diary

D.

medical magazine

As the fifth of seven children, I went to the same public school as my three elder sisters and brother.Every year, each child from the third grade took part in an old school tradition﹣the plant sale held in early May, just before Mother's Day.

That year I was old enough to take part in it. I wanted to surprise my mother, but I didn't have any money. I told my elder sister about it and she gave me some money. When I arrived at the plant sale, I carefully chose my favorite. I watched each plant seriously to make sure that I could find the best geranium(天竺葵). After school, with the help of my sister I bid it on the neighbor's porch(门廊).On Mother's Day, I remember how bright my mother's eyes were and how   alated  she was at my gift.

The year I was fifteen, my younger sister reached the third, grade. She told me that, she wanted to

surprise our mother. Like my elder sister did for me, I gave her some money. And she bought the same gift and we hid it in the same place. When she gave the gift to my mother, I watched them full of pride and happiness. My mother noticed me watching and gave me a soft and secret smile. With a shock at my heart, I smiled back.

I wonder how my mother could pretend (假装) to be surprised at the same sixth child, but as I watched her eyes, I knew she was not pretending.

(1)The writer first took part in the plant sale   

A.

in the third grade

B.

at the age of sixteen

C.

in the fifth grade

D.

at the age of fifteen

(2)The underlined word "elated" in the second paragraph probably means   

A.

angry

B.

upset

C.

excited

D.

relaxed

(3)The sixth child bought   for her mother.

A.

the prettiest rose

B.

the best geranium

C.

the biggest grape

D.

the freshest strawberry

(4)From the third paragraph, we can know the mother   when she got the same gift.

A.

refused to accept it

B.

pretended to be happy

C.

felt proud and happy

D.

hid it on the neighbor's porch

(5)The passage is mainly about   

A.

the best place to hide a gift

B.

a good way to surprise mom

C.

an awful secret of the family

D.

deep love between mom and children

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