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Another problem is the strain that a person is subjected to when a rocket leaves the ground. Anything that is not moving tends to resist movement. As the rocket leaves the ground, it pushes upward, and the person is pushed back against the chair. During this thrust, gravity exerts a force on the body equal to nine times its normal force.
Once out of the earth's gravity an astronaut is affected by still another problem—weightlessness. Here, if a pencil drops, it doesn't fall. If a glass of water is turned upside down, the water will not fall out. All of us who are used to gravity expect things to have weightless conditions. Recent long flights have shown that the body needs special exercise in a spaceship.
l. As a rocket leaves the ground, an astronaut experiences a force called——.
A. gravity B. a push
C. downward force D. strain
2. The force of gravity an astronaut is subjected to when the rocket leaves the ground is equal to
A. 7 times its downward force B. 5 times its normal force
C. 3 times its upward force D. 9 times its normal force
3. Which of the following is not true according to the passage?
A. Everything is down to the earth by magnetic force.
B. Recent long flights have shown that the body needs special exercise in spaceship.
C. A rocket must go at most 2, 500 miles an hour to take anyone beyond the gravity of the earth into space.
D. There are many problems connected with space travel.
4. Which is the best title for this passage?
A. Weightlessness. Gravity and Strain Are All too Difficult to Understand
B. Gravity is the Enemy of Space Travel
C. Space Travel Problems
D. People Cannot Leave the Earth Because of the Air
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There are many problems connected with space travel. The first and greatest of them is gravity (地球引力). If you let your pencil drop to the floor, you can see gravity in action. Everything is down to the earth by magnetic force. The weight of something is another way of describing the amount of force exerted on it by gravity. A rocket must go at least 2, 500 miles an hour to take anyone beyond the gravity of the earth into space.
Another problem is the strain that a person is subjected to when a rocket leaves the ground. Anything that is not moving tends to resist movement. As the rocket leaves the ground, it pushes upward, and the person is pushed back against the chair. During this thrust, gravity exerts a force on the body equal to nine times its normal force.
Once out of the earth's gravity an astronaut is affected by still another problem—weightlessness. Here, if a pencil drops, it doesn't fall. If a glass of water is turned upside down, the water will not fall out. All of us who are used to gravity expect things to have weightless conditions. Recent long flights have shown that the body needs special exercise in a spaceship.
l. As a rocket leaves the ground, an astronaut experiences a force called——.
A. gravity B. a push
C. downward force D. strain
2. The force of gravity an astronaut is subjected to when the rocket leaves the ground is equal to
A. 7 times its downward force B. 5 times its normal force
C. 3 times its upward force D. 9 times its normal force
3. Which of the following is not true according to the passage?
A. Everything is down to the earth by magnetic force.
B. Recent long flights have shown that the body needs special exercise in spaceship.
C. A rocket must go at most 2, 500 miles an hour to take anyone beyond the gravity of the earth into space.
D. There are many problems connected with space travel.
4. Which is the best title for this passage?
A. Weightlessness. Gravity and Strain Are All too Difficult to Understand
B. Gravity is the Enemy of Space Travel
C. Space Travel Problems
D. People Cannot Leave the Earth Because of the Air
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根据对话内容，从对话后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。
Holly Porter is the owner of a small company, Porter Printing Co．With the help of her secretary, Lizzy, she is arranging a 10th-anniversary staff dinner．
P－Porter L－Lizzy
P：Now that we’ve arranged the time and place, we can write the invitation．
L： 1
P：How about this“To celebrate 10 years in business, Holly Porter requests the honor of your presence at…” 2
L：It just sounds very formal．
P：What do you suggest, then?
L：How about this：“After 10 years at Porter Printing, it’s time to celebrate!Join us at…”
P：That does sound better．
L：Should the invitation include children, Ms．Porter?
P： 3
L：How would you like to say that, then?
P：I guess we can’t say,“No kids, please,”can we?
L： 4 How about just addressing the invitation to“employee and guest”?
P： 5
A．No, no．I don’t mind．
B．That sounds fine．I hope they get the hint(暗示)．
C．What would you like it to say?
D．What’s the matter?You don’t like this?
E．No．Not this time．
F．That may not sound very nice．
G．That would be fine with us．
Here are some of the world’s most impressive subways
| The Tokyo Metro and Toei Lines | Features: The Tokyo Metro and Toei lines that compose Tokyo’s massive(庞大的)subway system carry almost 8 million people each day, making it the busiest system in the world. The system is famous for its oshiya— literally, “pusher”— who pushes passengers into crowded subway cars so the doors can close. And you think your commute (上下班路程) is hell. |
| The Moscow Metro | Features: The Moscow Metro has some of the most beautiful stations in the world. The best of them were built during the Stalinist era and feature chandeliers(枝形吊灯), marble moldings and elaborate murals(精美的壁画). With more than 7 million riders a day, keeping all that marble clean has got to be a burden. |
| The Hong Kong MTR | Features: The Hong Kong MTR has the distinction of being one of the few subway systems in the world that actually turns a profit. It’s privately owned and uses real estate development along its tracks to increase income and ridership. It also introduced “Octopus cards” that allow people to not only pay their fares electronically, but buy stuff at convenience stores, supermarkets, restaurants and even parking meters. It’s estimated that 95 % of all adults in Hong Kong own an Octopus card. |
| Shanghai Metro | Features: Shanghai is the third city in China to build a metro system, and it has become the country’s largest in the 12 years since it opened．Shanghai Metro has 142 miles of track and plans to add another 180 miles within five years. By that .point, it would be three times larger than Chicago “L”. The system carries about 2.18 million people a day. |
| The London Metro | Features: Londoners call their subway the Underground, even though 55 percent of it lies above ground. No matter when you’ve got the oldest mass-transit system in the world, you can call it anything you like．Trains started in1863 and they’ve been running ever since. Some 3 million people ride each day, every one of them remembering to “Mind the gap”. |
60. Which one can provide the riders some wonderful decorations at the stations?
A. The Tokyo Metro and Toei Lines B. The Moscow Metro
C. The London Metro D. The Hong Kong MTR
61. ________ is done with the purpose of making money．
A. The Tokyo Metro and Toei Lines B. The Moscow Metro
C. The London Metro D. The Hong Kong MTR
62. We can learn from the passage that Shanghai Metro____________．
A. carries the most people each day B. is the world’s largest
C. may be larger than the Chicago “L” in the future D. is the busiest in the world
63. What do we know about the Hong Kong MTR?
A. It is not owned by state. B. It has become the country’s largest subway since it opened.
C. It carries the most people every day . D. It is the busiest system in the world.
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That“Monday morning feeling”could be a crushing pain in the chest which leaves you sweating and gasping for breath. Recent research from Germany and Italy shows that heart attacks are more common on Monday mornings and doctors blame the stress of returning to work after the weekend break.
The risk of having a heart attack on any given day should be one in seven, but a six-year study helped by researchers at the Free University of Berlin of more than 2, 600 Germans showed that the average person had a 20 percent higher chance of having a heart attack on a Monday than on any other day.
Working Germans are particularly not protected against attack, with a 33 percent higher risk at the beginning of the working week. Non-workers, by comparison, appear to be no more at risk on a Monday than any other day.
A study of 11, 000 Italians proved 8 a. m. on a Monday morning as the most stressful time for the heart, and both studies showed that Sunday is the least stressful day, with fewest heart attacks in both countries.
The finding could lead to a better understanding of what is the immediate cause of heart attacks, according to Dr Stefan Willich of the Free University. “We know a lot about long-term risk factors such as smoking and cholesterol（胆固醇）but we don’t know what actually causes heart attacks, so we can’t give clear advice on how to prevent them, ”he said.
Monday mornings have a double helping of stress for the working body as it makes a rapid change from sleep to activity, and from the relaxing weekend to the pressures of work.
“When people get up, their blood pressure and heart rate go up and there are hormonal（内分泌）changes in their bodies, ”Willich explained. “All these things can have an unfavorable effect in the blood system and increase the risk of a clot（血凝块）which will cause a heart attack.”
“When people return to work after a weekend off, the pace of their life changes. They have a higher workload, more stress, more anger and more physical activities,”said Willich.
1.Monday morning feeling, as this passage shows, ________.
|
A．is not as serious as people thought |
|
B．is the first killer in Germany and Italy |
|
C．is created by researchers in Germany and Italy |
|
D．is harmful to working people in developed countries |
2.To protect people from a heart attack, doctors have paid much attention to ________.
|
A．people’s working time |
B．people’s living place |
|
C．people’s diet and lifestyle |
D．people’s nationalities |
3.It can be learned from this passage that the heart attack has something to do with all the following EXCEPT ________.
|
A．blood pressure |
B．heart rate |
C．hormonal changes |
D．blood type |
4.If the researchers give us some advice to avoid Monday morning feeling, what might it be?
|
A．Improve working conditions. |
B．Never go to work on Mondays. |
|
C．Stay with a doctor on Mondays. |
D．Get up late on Monday mornings. |
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