In today’s world, sleep experts say that for a better night’s rest, Americans should turn off their smartphones or iPad before sleeping. Such electronic products make the brain more active, and then influence their sleep. But according to a latest survey, more than 90% of Americans regularly use a computer or some other kinds of electronic products in the hour before bed.
Researchers are finding that man-made light from some electronic products at night may reduce the brain chemicals(化学物质) that help sleep. The researchers showed that sitting in the light from computer tablets clearly lowered levels of the chemical which manages our body clocks and plays a role in the sleep cycle.
In the study, the researchers let volunteers read, play games and watch movies on a tablet for different time while measuring(测量) how much light their eyes received. They found that two hours of sitting before a bright tablet screen at night reduced the sleep chemical levels by about 22%.
Studies of students using computers at night have got the similar results. And researchers say that may not only cause sleeplessness, but also raise the risk of obesity(肥胖症), diabetes(糖尿病) and other diseases.
To be on the safe side, the researchers advise us to use computers less before bed, or at the very least turning down your screen as much as possible.
1. What can we learn from the first paragraph?
A. Americans don’t get enough sleep.
B. Electronic products are very popular.
C. The brain becomes more active at night.
D. Sleep experts never use smartphones.
2.The volunteers in the study did the following things EXCEPT _____.
A. listening to music
B. playing computer games
C. watching movies
D. reading electronic books
3. The underlined word “that” probably means ____ in the passage.
A. making a survey about sleep
B. using smartphones in the daytime
C. sitting in a bright room
D. surfing the Internet at night
4.What does the passage tell us to do to have a good sleep?
A. Learn to use smartphones or iPad.
B. Watch some relaxing TV programs.
C. Turn down the screen to the lowest.
D. Try to sleep earlier than before.
According to the studies from the UN, the increase of CO2 in the air is responsible for 85% of the temperature increase. CO2 goes into the air when we burn fossil fuels to run our industries, cars and so on. Luckily, half of the CO2 that we produced is taken in by plants, trees, land and the oceans. The rest gases are still large to cause worry. At the same time, we are cutting down forests that take in carbon from the air.
To solve the problem is not an easy job. Developed nations such as the USA, Germany and Australia will have to promise to cut down greenhouse gases by as much as 25-40%. Countries such as India and China that have a large population and growing industry, have to leave a smaller greenhouse gas footprint. Everybody must be active and stick to it.
1. Half of the CO2 that we produced can be taken in by ___________.
A. plants and trees B. land
C. the oceans D. A, B and C
2. Why does the temperature increase?
A. People use up useful gases.
B. More and more CO2 goes into the air because of people’s activities.
C. Forests can not take in CO2 any more.
D. Everybody hopes winter can be warm.
3.How many countries are mentioned in this passage?
A. 2 B. 3 C. 5 D. 6
Kobe Bryant is the son of former NBA player Joe Bryant, and was born in 1978 in Philadelphia. Even though his grades were good, the younger Bryant chose to join the NBA after high school.
Del Harris, the coach of Lakers, brought Kobe into his first NBA game when he was only 18 years old. Over the next three seasons, Bryant showed plenty of ability.
The following three years ---- 2000, 2001, and 2002 were the golden years for the Lakers. Kobe Bryant and Shaquille O’Neal formed a dream partnership, and the Lakers won three straight championships. Kobe also won a gold medal at the Olympics with Team USA in 2008.
However, in 2015, everybody knew that the Lakers era(时代) came to an end. Kobe had led his team to amazing heights, but his time was coming to an end. On November 29, 2015, Kobe announced that he would retire at the end of the season.
1.Bryant chose to join the NBA because of his bad grades.
2.As a basketball player, Kobe never lost a game.
3.Kobe’s team won a gold medal at the Olympics in Beijing.
4.Kobe’s father used to be a basketball player.
5.The passage tells us Kobe’s lifetime.
完形填空
阅读下面一篇短文，理解大意，然后从各小题的四个选项中选出一个最佳答案，使短文连贯完整。
One’s attitude is always important. If you are lazy and weak, you will never taste success. But if you are ______ , success and happiness will be more likely to come to you.
I love eating persimmons (柿子) . But you can’t get them until autumn. If you try them before the right time, they probably ______ bad. In Grade Six, because of my poor grades, my parents were ______ that I wouldn’t be able to get into an excellent middle school. They______ me to study harder, but I didn’t really understand why they were so anxious(焦虑的).
Summer came and I studied hard. The hot weather made me sleepy and I couldn’t concentrate (集中精力) on my textbook. But every time when I wanted to stop ______ , my dad would say, “Think about your ______ . If you don’t work hard, you will regret.” I had to sit back down again and return to my textbooks. But all I ______ was playing with my friends.
My dad would say to me, with a serious look on ______ face, “If a persimmon tree doesn’t grow in summer, it can’t bear (结出) fruit in autumn! Only by working hard can you get good results.” A few months later, I succeeded in ______ the key middle school. I was so happy. My dad was right, if a persimmon tree doesn’t grow ______ summer, there will be no fruit in autumn. I worked hard and I enjoyed the fruit of my hard work!
1.A. busy B. clever C. hard-working D. free
2.A. look B. taste C. turn D. smell
3.A. embarrassed B. worried C. excited D. annoyed
4.A. made B. allowed C. pushed D. pulled
5.A. thinking B. working C. playing D. looking
6.A. future B. hobby C. health D. wealth
7.A. talked about B. heard about C. thought about D. throw about
8.A. his B. your C. my D. their
9.A. failing B. reaching C. getting D. entering
10. A. before B. during C. after D. until
A speaking competition for the coming term _______ next week.
A. is held B. will hold
C. holds D. will be held
---- What did Joe and Kate ask just now?
---- They wondered _______.
A. that they could take something to drink
B. when would they start
C. if they would meet in front of the post office
D. how they can get there
