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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 behavior. 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 is stronger than 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.

1.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.

2.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.

3.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.

4.What is mainly discussed in the passage?

A. experiments about how ants manage to keep their nests clean.  

B. experiments about why ants have special chemicals on their bodies.

C. experiments about why ants can have this removal behavior

D. experiments about how to decide whether an ant is dead or not.

 

With healthy self-confidence you’ll take more chances and overcome obstacles faster. How do you boost your self-confidence? Here are some easy-to-try-out trips.

Speak well of yourself. We become what we think about most of the time. 1. If you continually tell yourself you “can’t do something”, you’re sure to create that reality for yourself, because that is how you see yourself. On the other hand, if you repeatedly say and think to yourself something like, “I am capable of creating a life I love”, soon you will begin creating a life you love.

Surround yourself with self-confident people and positive environments. It sounds a bit obvious, but if you have friends that lack confidence, you probably do too. If you’re surrounded by people who criticize others and speak poorly of themselves, get out! Remove yourself from their company.  2. Seek out friends who are confident and you’ll feel your confidence increasing.

 3. Don’t say you’re going to do something unless you really intend to do it. We’ve all met the “big talkers” – people who talk about their big plans but never do anything to make them happen. The “big talkers” lose face because no one believes they’ll do what they say they’re going to do.

Accept fear and obstacles as a natural part of life and growth. Don’t beat yourself up when you find yourself gripped(抓住) by fear and other emotions. 4.Be aware when these feelings are present but don’t let them stop you. Keep moving forward by telling yourself you’re much more than the obstacles you face and failures you experience.

 5. Once a month, take a few moments to write down all that you have done well. Acknowledge the work you do and your strengths on a regular basis. In doing so, you’ll begin seeing and appreciating all the good you do.

A．Start with small steps.

B．We become what we say about ourselves.

C．Negative environments are hard to escape.

D．Don’t judge yourself for having these feelings.

E. In fact, no company is better than bad company.

F. Take action on what you say you’re going to do.

G. Take time out to focus on all that you have done well.

 

Plastic is everywhere because plastic is an extremely useful material. It is cheap, strong and lightweight. What’s more, it can take on nearly any form or shape, from soft and stretchy (有彈性的) to hard and glasslike.

Plastic, however, is far from perfect. It may even be bad for us. Studies now suggest that poisonous chemicals can get out of some types of plastic, get into our bodies, and cause a variety of health problems, including cancer, birth defects and attention deficit hyperactivity disorder (注意缺陷障礙).

Two types of chemicals in particular have raised special concern lately. They are called phthalates (鄰苯二甲酸鹽) and Bisphenol-A (二酚基丙烷), BPA for short. Not all plastic products contain them. But the ones that do are surrounded by controversy (爭議). That’s because experts disagree on how dangerous these chemicals are.

Plastic is a single word, but plastic isn’t just one thing. What all plastics share in common are plasticizers -- special chemicals that allow the material to be changed into nearly any shape or texture. Plasticizers (塑化劑) are added to plastic during the manufacturing process.

Phthalates and BPA are two types of plasticizers that work in different ways. Phthalates add softness to things like shampoo bottles, raincoats and rubber. They are also used in perfumes and makeup. BPA, on the other hand, gives a hard, clear, almost glasslike feel to products such as infant bottles. BPA also appears in food and soda cans, DVDs and other unexpected places.

How do these chemicals get into us? When plastic is heated in the microwave or dishwasher, chewed on or scratched, the chemicals can seep (滲透) out of the plastic. Even though we can’t see them, we eat them, drink them and breathe them in.

Scientists and parents are especially worried about young children, who tend to chew on everything, including plastic. Dozens of countries, including the European Union, Japan, Canada and Mexico have already banned phthalates from products made for children younger than three. California and Washington have done the same. And a number of other states are considering similar rules. As for BPA, Canada became the first country to ban the chemical from baby bottles. A dozen states are considering it.

1.What can we know about the plastic from the first paragraph?

A. Its characters and effects.                   B. Its wide use and bad points.

C. Its importance and chemicals.               D. Its popularity and advantages.

2.Which of the following products contains BPA?

A. A soft plastic cup.                           B. A pencil eraser.

C. A baby milk bottle.                            D. A new perfume.

3.Phthalates and BPA can get into us __________.

A. through mouth or nose                          B. through blood transfusion

C. by feeling plastic products                  D. by heating in the microwave

4. What is the passage mainly about?

A. A new ban on plastic products.             B. Problems caused by the plastic. 

C. Good points of the plastic.            D. The use of plasticizers.

 

-----How do you find the book?    ------_____________.

A. Great.   B. With the help of my brother.

C. By looking around.D.By chance.

 

Directions: Read the following passage.Answer the questions according to the information given in the passage and the required words limit.

Many people pursue goals that they hope will make them happy, but happiness is not always the final result. So how does one determine and establish which goals will end in personal happiness and which will not ? what are the things in life that are correlated with personal happiness?

The most important thing is people’s attitude toward life, which can greatly impact their personal levels of happiness and satisfaction with life overall.

Psychologists have known for some time that optimism is a good defense against unhappiness. It’s probably no secret that optimistic people are considered to be much more happier people than pessimists. There are specific characteristic features optimists have (pleasant ways of thinking), that bring them more success, greater health, increased life satisfaction, and other good things. If you became an optimist, it can mean that you became a very happy person, despite your circumstances, and it can actually bring more things into your life to be happy about. “If you are optimistic and you think life is going to get better, it will become a self-fulfilling prediction”, says one of the scientists. “Happy people manage to look on the bright side, even if they encounter big problems on their way.”

Positive psychologists believe that people can learn how to become happy, that everyone can teach themselves to see a half-empty glass as half-full. All they have to do is to spend time thinking about all the things that have gone right for them, rather than complaining what has gone badly. Study on depression shows that one of the biggest causes of depression is thinking and worrying about something that went wrong in the past.

1.According to the passage, what can affect people’s personal levels of happiness? (No more than 5 words ) (2 marks)

_________________________________________________________________.

2.Why are some people depressed according to the study? (No more than 13 words )  (2 marks)

_____________________________________________________________.

3.How do people learn to be happy according to the psychologist ? (No more than 15 words )  (3 marks)

________________________________________________________________.

4.What is the main idea of the passage? (No more than 10 words )   (3 marks)

______________________________________________________________.