When an ant dies, other ants take it out of the nest, often within an hour after its death. This behavior interests scientists and they wonder how ants know for sure—and so soon—that another ant is dead.
One scientist recently came up with a way to explain this ant behaviour. Dong-Hwan Choe is a biologist, a scientist who studies animals and plants. He found that ants have a chemical on the outside of their bodies that signals to other ants, “I'm dead—take me away” when it is dead.
But there's a question to answer: As we know, if an ant is dead, it stops moving. But when an ant is sleeping or knocked unconscious, it is also not moving. However, other ants don't move the living ant out of the nest. How do they know this ant is not dead? Choe found that ants have another chemical on their bodies, which tells nearby ants something like, “Wait—I'm not dead yet” when it is not dead. Choe suspects that when an ant dies, the chemical that says, “Wait I'm not dead yet” quickly goes away. When other ants detect the “dead” chemical without the “not dead yet” chemical, they move away the body.
To test his theory , Choe and his team put different chemicals on ants. When the scientists used the “I'm dead” chemical, other ants quickly moved the treated ant away. When the scientists used the “Wait—I'm not dead yet” chemical, other ants left the treated ant alone. Choe believes this behavior shows that the “not dead yet” chemical overrides the “dead” chemical when picked up by other ants. And that when an ant dies, the “not dead yet” chemical fades away. Other nearby ants then detect the remaining “dead” chemical and remove the body from the nest.
Understanding this behavior can help scientists figure out how to stop ants from invading new places and causing problems.What is the function of the first paragraph?
| A．Leading the following paragraphs. |
| B．Showing the main idea of the passage. |
| C．Introducing the background of the passage. |
| D．Giving a summary of the passage. |
Which of the following has the closest meaning to the underlined word “overrides” in the fourth paragraph?
| A．is weaker than | B．is stronger than |
| C．is better than | D．is worse than |
What can we learn from the passage?
| A．Living ants can also be taken away when they are not moving. |
| B．When an ant dies, it can tell others using a certain chemical. |
| C．A living ant can pretend to be dead using a special chemical. |
| D．Ants often use chemicals to communicate with each other. |
Which of the following descriptions about Dong-Hwan Choe is right?
| A．Choe did this study in order to stop ants from invading new places. |
| B．Choe is a biologist who is only interested in animals, especially in ants. |
| C．Choe first came up with an idea to explain this ant behavior，and then did some tests to prove his theory. |
| D．Choe did the research on this ant behavior on his own |
Have you ever noticed what happens to an idea once you express it? Just talking about it or writing it down causes you to make it clear in your own mind. How can you use this to increase your brain power? Start writing.
By putting thoughts into words, you are telling yourself the logic (逻辑) behind what you think, feel, or only partly understand. Often, explaining a thought is the process of understanding. In other words, you increase your brain power by exercising your “explain power.”
Try this experiment. Explain how you’ll increase your brain power, even if you have no idea how right now. Just start with anything, and create an explanation. For example, start with “I’ll learn chess,” or “I’ll read an article on the mind every week.” Explain how that will help. You’ll be surprised how often this becomes a workable plan, and if you actually do this, you’ll have a better understanding of your brain twenty minutes from now.
Another benefit of writing is that it helps you remember. Many, if not most, highly productive people are always taking notes. You can try keeping it all in your head, but if you keep a journal of your ideas the next time you’re working on a big project, you’ll probably have more success.
Want to understand a topic? Write a book about it. That’s an extreme example, but if you are learning something new, write a letter to a friend about it, and you will understand it better. Want to invent something? Write an explanation of the problem, why you want to solve it, and why it is worth solving, and you’re half-way there.
Writers don’t always write because they clearly understand something beforehand. Often, they write about something because they want to understand it. You can do the same. Writing will help bring you to an understanding. Give it a try.What would be the best title for the text?
| A．A Way on How to Write |
| B．Increase Your Brain Power through Writing |
| C．Brain Power Helps Improve Your Writing |
| D．How to Start Your Writing |
If a writer writes something, it means that he or she _______.
| A．has understood it very well |
| B．needs to understand it better |
| C．wants to remember it in his or her mind |
| D．is exercising his or her “explain power” |
The underlined sentence “you’re half-way there” in the fifth paragraph implies that ______.
| A．you are already successful |
| B．you still need to work hard |
| C．writing can help you walk half way |
| D．you have been on the way to success |
What’s the main purpose of the writer writing the text?
| A．To advise readers to start their writing. |
| B．To explain the importance of writing. |
| C．To persuade readers to become writers. |
| D．To increase readers’ brain power. |
Obama Still Smokes in Secret
US President Barack Obama has just made life more difficult for cigarette makers. He has just signed a law that will set tough new rules for the tobacco industry. The new law gives the US Food and Drug Administration the power to strictly limit the making and marketing of tobacco products.
At a White House signing ceremony Monday, Obama said that he was among the nearly 90% of smokers who took up the habit before their 18th birthday.
Obama, who has publicly struggled to give up smoking, said he still hasn’t completely kicked the habit. Every now and then he still smokes in secret.
“As a former smoker I struggle with it all the time. Do I still smoke sometimes? Yes. Am I a daily smoker, a constant smoker? No.” Obama said at a news conference.
“I don’t do it in front of my kids. I don’t do it in front of my family. I would say that I am 95% cured, but there are times when I mess up,” he said.
“Once you go down this path, it’s something you continually struggle with, which is exactly why the law is so important. The new law is not about me, it’s about the next generation of kids coming up. What we don’t want is kids going down that path.” he said.
Nearly 20% of Americans smoke and tobacco use kills about 440,000 people a year in the United States due to cancer, heart disease, and other serious diseases.The new law makes life difficult for ________.
| A．Obama | B．tobacco industry |
| C．White House | D．US Food and Drug Administration |
What do we know about Obama?
| A．He no longer smokes. |
| B．He still smokes as usual. |
| C．He began to smoke at eighteen. |
| D．He is trying hard to give up smoking. |
According to the passage, Obama is most concerned about ________.
| A．children | B．officials |
| C．his family | D．businessmen |
Last week, I bought an alarm system for about $ 450. It consisted of a control unit with three small units. I put the control unit in the sitting-room and fastened the other units by the front door, back door and living-room windows. The instructions told us to choose three numbers, so we chose 491, the last three numbers of our telephone number.
Now I will explain how the alarm works:
1. There is a power siren in the control unit. It makes a very loud noise.
2. Each of the small units sends out beams or rays in different directions. If anything moves, it breaks a beam. This sends signal to the control unit. The siren makes a noise which you can hear 50 meters away.
3. When we go to bed, I press the three buttons numbered 4, 9 and 1. Then we have 30 seconds to get out of the room before the alarm starts to work. That night I slept soundly because I was sure that no burglar could get into our house. However, at about 2:10 a. m. , I woke up and heard the siren.
"There must be a burglar in the house?" Mary said, "What shall we do?"
"I'll go and see who's there," I said, "Stay here. Don't make a noise. "
I went down stairs quietly. When I reached the living-room, I switched on my torch and looked round the room. Then I turned the light on. I switched the siren off and searched the rooms downstairs. There was nothing wrong except that the back door was unlocked. I locked it, re-set the alarm and went back to bed.
About an hour later, the alarm started again. I jumped out of bed, fell over a chair in the dark and bumped into the bedroom door. Mary woke up and started hitting me with a torch. "Hey! Wait a minute!" I whispered, "It's only me. I'm going downstairs to see what's wrong."
I went down into the living-room and listened for a moment. The only sound I could hear was the siren. I tamed on the light and switched the siren off. As I did so, I glanced across at the curtains in front of the windows. I saw a house lizard (a kind of small animals)(壁虎) disappear behind the curtains.
"Oh!" I said to myself. "That's our burglar.”
When the lizard moved, it started the siren. I guessed the alarm had been made in Europe, where there are no house lizards.
Well, I won't finish this story but if you want an alarm system free of charge, let me know. I'll send you ours. We bought a dog this morning. It knows the difference between a lizard and a burglar(强盗).The writer bought an alarm system to_________.
| A．make sure that he got up early every day |
| B．warn him when there were lizards in his house |
| C．frighten burglars and tell him that somebody had got into the house |
| D．make Mary feel safe to live in the large room |
The writer used numbers 4, 9 and 1 to________.
| A．set the alarm system |
| B．make a telephone call |
| C．give numbers to each of the three units in the downstairs rooms |
| D．name his alarm system |
The purpose of the three units was to_________.
| A．sound their own siren when the control unit told them to |
| B．send a message to the control unit and start the siren |
| C．check that the control unit worked properly all the time |
| D．give them enough light |
If the writer set the alarm and remained in the room for more than half a minute,__________.
| A．nothing would happen |
| B．the control unit would not work |
| C．the siren would make a noise |
| D．the dog would bark |
The purpose of the writer in writing the passage is to__________.
| A．tell us that the alarm system doesn't work |
| B．make it clear that he wants to give away his alarm system |
| C．show us how the alarm system works |
| D．tell us an interesting experience |
I found out one time that doing a favor for someone could get you into a lot of trouble. I was in the eighth grade at the time, and we were having a final test. During the test, the girl sitting next to me whispered something, but I didn’t understand. So I leaned over her way and found out that she was trying to ask me if I had an extra pen. She showed me that hers was out of ink and would not write. I happened to have an extra one, so I took it out of my pocket and put it on her desk.
Later, after the test papers had been turned in, the teacher asked me to stay in the room when all the other students were dismissed（解散）. As soon as we were alone she began to talk to me about what it meant to grow up; she talked about how important it was to stand on your own two feet and be responsible for your own acts. For a long time, she talked about honesty and emphasized（强调） the fact that when people do something dishonest, they are really cheating（欺骗） themselves. She made me promise that I would think seriously（认真地） about all the things she had said, and then she told me I could leave. I walked out of the room wondering why she had chosen to talk to me about all those things.
Later on, I found out that she thought I had cheated on the test. When she saw me lean over to talk to the girl next to me, it looked as if I was copying answers from the girl’s test paper. I tried to explain about the pen, but all she could say was it seemed very strange to her that I hadn’t talked of anything about the pen the day she talked to me right after the test. Even if I tried to explain that I was just doing the girl a favor by letting her use my pen, I am sure she continued（继续） to believe that I had cheated on the test.The story took place（发生） exactly ____ .
| A．in the teacher’s office | B．in an exam room |
| C．in the school | D．in the language lab |
The girl wanted to borrow a pen, because ____ .
| A．she had not brought a pen with her |
| B．she had lost her own on her way to school |
| C．there was something wrong with her own |
| D．her own had been taken away by someone |
The teacher saw all this, so she asked the boy ____ .
| A．to go on writing his paper |
| B．to stop whispering |
| C．to leave the room immediately |
| D．to stay behind after the exam |
The thing(s) emphasized in her talk was(were) ____ .
| A．honesty | B．sense of duty |
| C．seriousness | D．all of the above |
The boy knew everything ____ .
| A．the moment he was asked to stay behind |
| B．when the teacher started talking about honesty |
| C．when he was walking out of the room |
| D．only some time later |
At 18, many American young people go off on their own. They go away to college or find full-time jobs, and they often rent their own apartments. Some get married and start families. This independence(独立性) is learned from childhood.
From an early age, American children learn responsibility（责任感）. Children as young as 2 begin to put away their toys and dress themselves. At 3, many children do simple chores like setting the table.
Using money wisely is also taught early. As soon as a child understands the value of money, he or she receives a weekly allowance. This is used for things the child wants, like toys or treats. The child can spend or save it, usually with little guidance（指导） from parents. If the child wants money besides his or her allowance, it must be made by doing extra chores.
Children are taught early in life to think for themselves. They are allowed to make some decisions—and make mistakes. Failure（失败）often teaches more than success.Many American young people begin to live on themselves __________.
| A．at eighteen years old | B．from childhood |
| C．after they get married | D．from an early age |
An American child learns to __________ at the age of 2.
| A．find a full-time job |
| B．rent an apartment |
| C．put on his or her own clothes |
| D．do lots of chores |
The word “allowance”（in paragraph 3）means __________ in Chinese.
| A．零花钱 | B．奖品 | C．财产 | D．礼物 |
A child can get some more money by __________.
| A．understanding the value of money |
| B．helping the rich |
| C．reading many books |
| D．doing extra chores |
The passage is mainly about __________.
| A．the guidance from parents |
| B．the value of money |
| C．the independence of American children |
| D．failure and success of American children |
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