Both warm-blooded and cold-blooded desert animals have ways to escape the desert heat. Warm- blooded desert animals, such as rats and mice, rest during the day, often staying in cool underground burrows. At night they search for food. Animals that are out during the day, such as cold-blooded lizards and snakes, are active only for short periods. As their body temperature rises, these reptiles(爬行动物) move into the shade in order to cool down. In the early evening, when the sun grows weaker, the reptiles become more active and begin their search for food again.
Getting enough water to survive is a major problem for all desert animals. Some desert animals, like desert birds, manage to find water holes. Other desert animals, such as the kangaroo rat and the related jerboa, get water only from the food that they eat. Because these animals eat mainly dry seeds, they must survive on a tiny amount of water.
Most deserts have only a small number of frogs and toads because these animals must be near water to survive. Yet even these creatures have adapted(适应) to desert conditions. When small amounts of water collect in temporary streams, the desert-living frogs and toads become active. After a rainfall, they lay their eggs. The eggs grow into tadpoles in a few days and into adults in just four weeks. When the puddles(水坑) dry up, the adult frogs or toads dig into the ground. Their metabolism(新陈代谢) slows, and they stay beneath the ground until the next rain, which may be as good as a year away. Until then, their bodily activities continue at a reduced rate.
The camel — often called the ship of the desert — is one of the most successful desert animals. Camels can go for long periods without water, but eventually they must drink. When water becomes available to them after a long drought, they may drink 95 liters of water or more. When water is not available, what helps camels survive the desert heat is the fat stored in their humps(驼峰). A camel’s hump contains about 12 kilograms of fat. Fat is rich in hydrogen. As the fat is digested, hydrogen from the fat combines with oxygen in the air that the camel breathes. The result is H2O, or water. Each kilogram of fat that a camel digests produces about a liter of water.
16.Desert animals are usually more active at night because _____.
A.it is cooler at night B.it is easier to find water
C.they like the dark D.they are less likely to be attacked at night
17.Which of the following desert animals can get water only from the food?
A.The camel. B.The kangaroo. C.The frog. D.The rat.
18.Which of the following is TRUE according to the passage?
A.All the desert animals rest during the day.
B.All the desert animals don’t rest during the day.
C.Cold-blooded desert animals are out most of the day.
D.None of the cold-blooded desert animals go out during the day.
19.The underlined word “burrows” in the first paragraph can be replaced by _____.
A.holes B.caves C.rooms D.openings
Professor Barry Wellman of the University of Toronto in Canada has invented a term to describe the way many North Americans interact(交流,沟通) these days. The term is “networked individualism”. This concept is not easy to understand because the words seem to have opposite meanings. How can we be individuals(个人,个体) and be networked at the same time? You need other people for networks.
Here is what Professor Wellman means. Before the invention of the Internet and e-mail, our social networks included live interactions with relatives, neighbors, and friends. Some of the interaction was by phone, but it was still voice to voice, person to person, in real time.
A recent research study by the Pew Internet and American Life Project showed that for a lot of people, electronic interaction through the computer has replaced this person-to-person interaction. However, a lot of people interviewed for the Pew study say that’s a good thing. Why?
In the past, many people were worried that the Internet isolated (孤立)us and caused us to spend too much time in the imaginary world of the computer. But the Pew study discovered that the opposite is true. The Internet connects us with more real people than expected—helpful people who can give advice on careers, medical problems, raising children, and choosing a school or college. About 60 million Americans told Pew that the Internet plays an important role in helping them make major life decisions.
Thanks to the computer, we are able to be alone and together with other people — at the same time!The underlined phrase “networked individualism” probably means that by using computers people ________.
A.stick to their own ways no matter what other people say |
B.have the rights and freedom to do things of their own interest |
C.do things in their own ways and express opinions different from other people |
D.are able to keep to themselves but at the same time reach out to other people |
According to the Pew study, what do many people rely on to make major life decisions?
A.Networks | B.Friends | C.Phones | D.Parents. |
It can be inferred from the Pew study that _______.
A.people have been separated from each other by using computers |
B.the Internet makes people waste a lot of time and feel very lonely |
C.the Internet has become a tool for a new kind of social communication |
D.a lot of people regard the person-to-person communication as a good thing |
Which would be the best title for this passage?
A.We’re Alone on the Internet. |
B.We’re Communicating on the Internet. |
C.We’re Alone Together on the Internet. |
D.We’re in the Imaginary World of the Internet |
Memory, they say, is a matter of practice and exercise. If you have the wish and really made a conscious(自觉的)effort, then you can quite easily improve your ability to remember things. But even if you are successful, there are times when your memory seems to play tricks on you.
Sometimes you remember things that really did not happen. One morning last week, for example, I got up and found that I had left the front door unlocked all night, yet I clearly remember locking it carefully the night before.
Memory “trick” work the other way as well. Once in a while you remember not doing something, and then find out that you did. One day last month, for example, I was sitting in a barber(理发师)shop waiting for my turn to get a haircut, and suddenly I realized that I had got a haircut two days before at the barber shop across the street from my office.
We always seem to find something funny and amusing(有趣的)in incidents caused by people’s forgetfulness or absent-mindedness. Stories about absent-minded professors have been told for years, and we never got tired of hearing new ones. Unfortunately, however, absent-mindedness is not always funny. There are times when “trick” of our memory can cause us great trouble.If you want to have a good memory, .
A.you should force yourself to remember things |
B.you should make a conscious effort of practice and exercise |
C.you should never stop learning |
D.you should try hard to remember tings |
Which of the following statements is true according to the passage?
A.One night the writer forgot to lock the front door. |
B.One night the writer forgot having locked the front door. |
C.The writer remembered to lock the door. |
D.the writer remembered unlocking the front door. |
In the passage, the writer seems to tell you .
A.forgetting things is serious and dangerous |
B.always forgetting things is understandable |
C.forgetting things at times is natural |
D.the way to protect yourself from memory “tricks” |
The best title for this passage is .
A.How to Get a Good Memory |
B.“Tricks” Of Memory |
C.Forgetfulness and Absent-mindedness is Dangerous |
D.Get Rid of Absent-mindedness |
Nearly 600,000 Americans lost their jobs this past month, pushing the nation’s unemployment rate (失业率) to 7.6 percent. But not all of those fired workers are sitting at home, reading the job advertisements and waiting for the phone to ring. Thousands of people are returning to school, making public colleges and universities among the few bright places in the disappointing US economy.
At a time when many Americans have had their work hours cut or have even lost their jobs, Sherian Huddleston is working overtime. She works at Middle Tennessee State University (MTSU) where she oversees (监督) the enrollment (注册) of new students. The university’s population grew by 800 students this term —an increase of 4 percent over last spring’s enrollment. Huddleston says seeing the enrollment rise in a failing economy is not unexpected. "When people are out of work," she points out, "they will ask 'What else can I do?’ or 'What other careers can I follow?’ They will often return to school if they have not completed a degree before."
Older returning students aren’t the only ones increasing the enrollment at MTSU. Huddleston says she’s also seeing an increase in student transfers (转移). "Students who went out of state, or even within the state, to more expensive schools are transferring to public schools to make use of the lower cost of going to school here," she explains.Which is the best title for the passage?
A.The Falling American Economy |
B.College Enrollment up in a Down Economy |
C.Colleges Have More Students Than Before |
D.Going to College Is No Longer Difficult |
According to the passage, many students return to school ______.
A.to make more money | B.to read job advertisements |
C.to complete a degree | D.to ask their schoolmates for help |
Many students are transferring to public schools mainly because ______.
A.public schools provide better education |
B.public schools offer better jobs to their students |
C.they don’t want to be influenced by the falling economy |
D.the cost of public schools is lower and they can save money |
Which of the following is TRUE about Sherian Huddleston?
A.She is working more hours than before because of the worsening economy. |
B.She is a student of Middle Tennessee State University. |
C.She disagrees with those who are returning to school. |
D.She is surprised to see the enrollment go up. |
I took my 9-year-old daughter,Suzan and 5-year-old son,Robbie to the shopping centre.As we got there,we saw a big sign that said,“Petting Zoo”.The kids jumped up and asked,“Daddy,can we go?”
Both my wife and I were out of work.However,I said,“Sure”,giving them a quarter each. They went away, leaving only fifty cents left in my pocket.
A petting zoo is made up of a hundred of little baby animals of all kinds.Kids pay their money and stay in the enclosure(围场)pleased with the little animals while their parents shop.
A few minutes later,I saw Suzan walking along behind me.I was surprised and asked what was wrong.
She said sadly,“Well,Daddy,a ticket for Petting Zoo costs fifty cents.So I gave Robbie my quarter.” Then she said the most beautiful thing I ever heard.She repeated the family motto(座右铭),which is “Love is Action!”
I knew clearly no one loves little animals more than Suzan. She had watched both my wife and me do and say "Love is Action!” for years,and now she had put it into her lifestyle.It had become part of her,because she knew the whole family motto.It’s not only “Love is Action”;it’s “Love is SACRIFICAL(牺牲的)Action!" Love always pays a price.
I was moved.We went back to the Petting Zoo.Suzan stood with her hands and chin(下巴)resting on the fence and just watched Robbie go crazy petting and feeding the animals.I had fifty cents burning a hole in my pocket. I put my hand into my pocket and took out the money.Sure,I must do that !What is the best title for this passage?
A.A Petting Zoo. | B.Try Your Best to Help Others. |
C.An Attractive Shopping Centre. | D.Love Is Sacrificial Action! |
The underlined part “the most beautiful thing” in Paragraph 5 refers to.
A.the Petting Zoo | B.the family motto |
C.their lifestyle | D.the ticket for Petting Zoo |
Which of the following best describes Suzan?
A.Unselfish. | B.Healthy. | C.Childish. | D.Clever. |
What might happen next according to the story?
A.The author would buy Suzan some candies. |
B.The author would get angry with Robbie. |
C.Suzan would play happily with the little animals. |
D.The author would play together with Suzan. |
A microscope is a useful instrument for observing small objects. By producing a bigger image, the microscope reveals details that are undetectable to the naked eye(裸眼).
Before using the microscope, please read the instructions below.
CAUTION: Microscopes are both delicate and expensive and must be handled with care.
1. Always carry the microscope with two hands — one supporting the base and the other on the arm.
2. Avoid stretching the wire of the lamp across a walkway.
3. Keep the stage clean and always use a glass slide for specimens(样本).
4. To avoid crushing the glass slide when focusing, begin with the lens close to the specimen and gradually back off to focus.
5. Keep the microscope covered to prevent the dust while it is being stored.
HOW TO USE THE MICROSCOPE:
1. Plug(接通电源) in the lamp.
2. Place a sample of what you wish to observe on a slide.
3. Adjust the mirror so it reflects light from the room up into the objective lens. When the mirror is correctly adjusted, a complete circle of light iwll appear when you look through the eyepiece.
4. Place your slide with the specimen directly over the center of the glass circle on teh stage. If it is a wet slide, be sure the bottom of the slide is dry.
5. With the LOW POWER objective leans placed over the slide, use the coarse focus knob to lower the lens to the lowest point.
6. Look through the eyepiece with one eye while closing the other eye. Slowly raise the lens until teh focus is relatively clear.
7. Use the fine focus knob to fine -tune(微调)the focus.
8. Without changing the focus knobs, switch to the HIGH POWER objective lens. Once you have switched to HIGH POWER, use only the fine focus knob to make the image sharper.Which of the following is the correct way to use a microscope according to the text?
A.Use one hand to carry the microscope |
B.Place a sample directly on the clean stage |
C.When stored, the microscope should be adjusted. |
D.Look through the eyepiece with one eye. |
If you want to observe a thin piece of hair, which of the following should you do first.?
A.Switch to objective lens. | B.Adjust the mirror. |
C.Look through the eyepiece. | D.Place the hair on a glass slide. |
According to the text, you could see a complete circle of light _____.
A.after correctly adjusting the mirror |
B.while looking at the specimen on a glass slide |
C.after slowly raising the objective lens |
D.before positioning the mirror correctly |