It is one of the greatest mysteries of nature. In case you haven’t noticed, all living things follow very definite, individual rhythms, all as regular as a clock, but what makes them regular? Though 题目和参考答案——青夏教育精英家教网—

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It is one of the greatest mysteries of nature. In case you haven’t noticed, all living things follow very definite, individual rhythms, all as regular as a clock, but what makes them regular?

Though many scientists maintain that these rhythms are the result of some outside force like gravity or radiation or both, the results of most scientific researches agree with other scientists who believe that each living thing has its own built-in biological “time clock.”

Take the mystery of migration for example. Scientists can’t really explain why many species of birds migrate in the autumn even though the temperature is still summery. The birds just seem to snub the comfortable weather that they are having. When a certain time comes, they travel south by the thousand. In spring time, they migrate northwards even though there probably is snow still covering the ground when they finally arrive. Something said “go,” and they did.

Animals that hibernate (冬眠) are obeying individual time clocks, too. When their clock indicates the time to take a winter’s nap, they do, and nothing can stop them. At a certain time in the spring, they wake up and come out regardless of the weather outside.

Plants appear to have yearly rhythms, such as the sprouting of seeds, and they also have daily rhythms. Notice sometimes that plants raise their leaves in daylight and lower them at night.

If you live along the California coast, you can easily observe a demonstration of this mysterious clock functioning regularly. There, from February to September, the highest tides occur exactly every fourteen and four-fifths days, and during these high tides, but at no other time, small silvery fish called grunions surf-ride a wave to the beach. There the female deposits her eggs in the sand and the male fertilizes them; then both hitch a wave-ride back to the sea. Exactly fourteen and four-fifths days later, never before or after, the tiny eggs hatch, and the high tide carries the new babies out to sea.

72. According to the passage, the mysterious rhythms result from ______.

A. the influence of gravity on living species

B. the effect of radiation on living species

C. the influence of a mysterious outer force on living species

D. the internal mechanism inside the living species

73. The underlined word “snub” in the third paragraph probably means ______.

A. fight B. ignore C. symbolize D. criticize

74. Which of the following statements is NOT TRUE?

A. Hibernating animals are obeying an internal time clock.

B. The positioning of the leaves of some plants is due to the daily rhythms.

C. The internal clock functioning is demonstrated in the reproducing habits of grunions.

D. The yearly hibernation is more because of the weather influence than the biological functioning.

75. The passage is mainly about ______.

A. the rhythms of life

B. the reasons of mysterious hibernation

C. strange behaviors of species

D. the timing for different events in the world of species

72----75 D B D A

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Some spiders hunt on the ground, others build webs to trap their food, but the grass water spider catches its prey by running along the surface of the water.

This special water spider lives on the grassy banks of streams where mosquitoes, damsel flies and other insects come to feed and breed.

Although it is one of the largest spiders in New Zealand, it has an unusual ability. It doesn’t disturb the water as it waits for its meal, and there is barely a ripple(波纹) when it skims(掠过) across the surface at lightning speed to catch its prey.

Grass water spiders deal swiftly with larger insects like damsel flies by pulling their heads under the water and holding them there until they drown.

After a meal, the grass water spider spends up to half an hour grooming(修饰) itself. It wipes its eight eyes, brushes its antennae(触角), and takes special care to clean the hairs on its body.

It is the hairs that trap tiny bubbles(泡沫) of air so that the spider can run down a blade(叶片) of grass and stay underwater for up to an hour when it is frightened. The hairs also keep the spider dry, even underwater.

It is only when the female spider is caring for the young that she does not hunt on the water. After mating, she produces a large egg sac(囊), which she carries around for five weeks. Once the eggs start to hatch, she attaches the sac to some blades of grass or a thistle. She then tears the sac open and releases the tiny spiders into the nursery web.

How does the grass water spider kill its prey?

A. in a web B. by drowning C. by poisoning D. with its antennae

the writer describes the special spider as “special” because _______.

A. it walks on water B. it has eight eyes　　

C. of its hairy appearance D. of the way it produces its young

The passage tells us that the spider ______.

A. feeds grass and thistles to its young.　　　　

B. lives on blades of grass under the water

C. lives in the grass on the banks of streams　　

D. eats a meal once every five weeks

The purpose of the passage is to _______.

A. convince readers that spiders are dangerous　　

B. indicate that the grass water spider is endangered

C. list all of the spiders that can be found in New Zealand

D. describe the characteristics of the grass water spider

In most cases, college graduates don't mind what job they will do so long as it is one ______ they can earn money to support themselves.

A. what????????????? ????????????? ?? ????????????? B. where????????????? ????????????? ????????????? ????????????? C. that????????????? ????????????? ????????????? ????????????? ????????????? D. how

How Americans Began to Eat Tomatoes

People have strange ideas about food. For example, the tomato is a kind of very

delicious vegetable. It is one of useful plants that can be prepared in many ways. It has rich nutrition and vitamin in it. But in the 18th century, Americans never ate tomatoes. They grow them in their gardens because tomato plants are so pretty. But they thought the vegetable was poisonous (有毒的). They called tomatoes “poison apples”.

President Thomas Jefferson, however, knew that tomatoes were good to eat. He was a learned man. He had been to Paris, where he learned to love the taste of tomatoes. He grew many kinds of tomatoes in his garden. The President taught his cook a way for a cream of tomato soup. This beautiful pink soup was served at the President’s party. The guests thought the soup tasted really good. They never thought their president would serve his honored guests poison apples. Jefferson never spoke to his honored (尊贵的) guests about the fact.

1.After you read the passage, which of the following do you think is true?

A．Americans never ate tomatoes after they began to plant them.

B．American didn’t eat tomatoes before the 19th century.

C．Even now Americans don’t eat tomatoes

D．In the 18^th century Americans ate a lot of tomatoes.

2.The passage tells us that Jefferson was a President who learned to love the taste of tomatoes.

A．while he was in Paris .

B．when he was a little boy.

C．the President ’s cook.

D．the President’s wife.

3.According to the text, ________cooked the beautiful pink soup at the President ’s party?

A．the President himself.

B．A French cook

C．the President ’s cook

D．the President’s wife

4.The underlined word “cook”in paragraph2 means_______

A．厨房 B．厨师 C．厨具 D．做饭

5.From the passage we know all the honored guests invited by Jefferson were______.

A．people from other countries B．from France

C．People of his own country D．men only

About this time every year, I get very nostalgic(怀旧的). Walking through my neighborhood on a fall afternoon reminds me of a time not too long ago when sounds of children filled the air, children playing games on a hill, and throwing leaves around in the street below. I was one of those children, carefree and happy. I live on a street that is only one block long. I have lived on the same street for sixteen years. I love my street. One side has six houses on it, and the other has only two houses, with a small hill in the middle and a huge cottonwood tree on one end. When I think of home, I think of my street. Only I see it as it was before. Unfortunately things change. One day, not long ago, I looked around and saw how different everything has become. Life on my street will never be the same because neighbors are quickly grown old, friends are growing up and leaving, and the city is planning to destroy my precious hill and sell the property to contractors.

It is hard for me to accept that many of my wonderful neighbors are growing old and won’t be around much longer. I have fond memories of the couple across the street, who sat together on their porch swing almost every evening, the widow next door who yelled at my brother and me for being too loud, and the crazy old man in a black suit who drove an old car. In contrast to those people, the people I see today are very old neighbors who have seen better days. The man in the black suit says he wants to die, and another neighbor just sold his house and moved into a nursing home. The lady who used to yell at us is too tired to bother any more, and the couple across the street rarely go out to their front porch these days. It is difficult to watch these precious people as they near the end of their lives because at once I thought they would live forever.

The “comings and goings” of the younger generation of my street are now mostly “goings” as friends and peers move on. Once upon a time, my life and the lives of my peers revolved around home. The boundary of our world was the gutter at the end of the street. We got pleasure from playing night games or from a breathtaking ride on a tricycle. Things are different now, as my friends become adults and move on. Children who rode tricycles now drive cars. The kids who once played with me now have new interests and values as they go their separate ways. Some have gone away to college like me, a few got married, two went into the army, and one went to prison. Watching all these people grow up and go away makes me long for the good old days.

Perhaps the biggest change on my street is the fact that the city is going to turn my precious hill into several lots for now homes. For sixteen years, the view out of my kitchen window has been a view of that hill. The hill was a fundamental part of my childhood life; it was the hub of social activity for the children of my street. We spent hours there building forts, sledding, and playing tag. The view out of my kitchen window now is very different; it is one of tractors and dump trucks tearing up the hill. When the hill goes, the neighborhood will not be the same. It is a piece of my childhood. It is a visual reminder of being a kid. Without the hill, my street will be just another pea in the pod.

There was a time when my street was my world, and I thought my world would never change. But something happened. People grow up, and people grow old. Places changes, and with the change comes the heartache of knowing I can never go back to the times I loved. In a year or so, I will be gone just like many of my neighbors. I will always look back to my years as a child, but the place I remember will not be the silent street whose peace is interrupted by the sounds of construction. It will be the happy, noisy, somewhat strange, but wonderful street I knew as a child.

1.The writer calls up the memory of the street _____________.

A. every year when autumn comes

B. in the afternoon every day

C. every time he walks along his street

D. now that he is an old man

2.The writer finds it hard to accept the fact that _____________.

A. many of his good neighbors are growing old

B. the lady next door who used to yell at him and his brother is now a widow

C. the life of his neighbors has become very boring

D. the man in his black suit even wanted to end his own life

3.The writer thinks of the past all the more when he sees those who had grown up with him _____________.

A. continue to consider home to be the center of their lives

B. leave the neighborhood they grew up in

C. still enjoy playing card games in the evenings

D. develop new interests and have new dreams

4.The biggest change on the writer's street is _____________.

A. removing the hill to make way for residential development

B. the building of new homes behind his kitchen window

C. the fact that there are much fewer people around than in the past

D. the change in his childhood friends' attitude towards their neighborhood

5.What does the writer mean by saying “my street will be another pea in the pod”?

A. his street will be very noisy and dirty

B. his street will soon be crowded with people

C. his street will have some new attractions

D. his street will be no different from any other street

6.Which could be a good title for the passage?

A. The Past of My Street will Live Forever

B. Unforgettable People and Things of My Street

C. Memory Street Isn't What It Used to Be

D. The Big Changes of My Street

短文改错

Dear Hou Ting,

I am sorry that maths disappoint you, but you can’t give it up.

As you say, it is one of the most important subject and there

is a reason for this. We have to use maths from all the time.

Wherever your career takes you, maths will have to be using.

In fact , most employers and universities will accept people

who have failed or given up maths. All you can do is try your

best in maths and make the most use of time you had. If you

have trouble understand anything, the first person you should

tell is your teacher. That is often surprising how simple things

seem when you are explained properly — even maths problems!

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