Most computer users think it necessary for their software regularly． A．to up date B．to be updated C．to have been up dated D．to have updated 题目和参考答案——青夏教育精英家教网—

题目内容

Most computer users think it necessary for their software ________ regularly．

A．to up date B．to be updated C．to have been up dated D．to have updated

【答案】

【解析】

试题分析：句意：大多数电脑使用者认为按时更新他们的软件是很必要的。这里it是形式宾语，不定式是真正的宾语，“他们的软件”和“更新”之间是被动关系，故用被动语态；且表示经常或反复发生的动作，故用不定式的一般式，选B。

考点：考查不定式的用法

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Another man-made wonder of the US was built long before the nation was established. About 900 years ago, the Ancestral Puebloan people built villages high in the walls of canyons（大峡谷）in Colorado, where 600 cliff dwellings are now part of the Mesa Verde National Park.

Visitors can stand at the top and look into the dwellings almost hidden in openings of the rock walls.The Puebloan people cut small steps into the rock, which connected buildings containing hundreds of rooms.

The rock walls have protected the buildings from severe weather in the area; therefore, they remain mostly unchanged in the hundreds of years since they were built.

Our final man-made wonder is in the northwestern city of Seattle, Washington. The Space Needle was built as the central structure for the 1962 World’s Fair.

The 184-meter-tall structure was designed by Edward Carlson, which has a wide base on the ground, with its middle narrow and a large ring-like structure on top.The structure was meant to look like a “flying saucer,” a vehicle that was popular in science fiction space travel stories. The saucer includes an observation area and eating place.The restaurant slowly turns to provide visitors with a 360 degree view of Seattle.

The Space Needle was not very costly, and was designed and completed in about a year and opened on the first day of the World’s Fair.

Today, the Space Needle is the most popular place for visitors to Seattle. And it remains the internationally known symbol of the city.

What can be talked about before the text?

A. American geography.

B. Touring in the USA.

C. Other US artificial wonders.

D. World natural wonders.

The underlined word “dwelling” is closest in meaning to “????????????________”.

A. houses B. people C. canyons D. steps

The buildings in the rock stay almost unchanged because________.

A. the weather there is severe

B. they were well built

C. people look after them well

D. the rock walls protect them

Which is true of the Space Needle?

A. It remains a symbol of the US.

B. Edward Carlson built the structure.

C. It has a ring-like structure on top.

D. It is a man-made wonder in Colorado.

What is the best title of the text?

A. Cultural Relics B. Artificial Wonders in the US

C. Symbols of Cities D. Natural Places in the US

D
A mysterious machine found in a 2,000-year-old Greek shipwreck may have been used to calculate the positions of planets, predict when eclipses (日、月蚀) were to occur, and study other parts of astronomy (天文学). When it was found underwater about 100 years ago, the machine was in poor shape. Its metal pieces had become one mass (堆), and then broke into pieces.
When the researchers began to study what was left of the machine, they thought it might have something to do with astronomy. To find out more, they recently used advanced imaging methods, including X-ray computer tomography (断层摄影术), to look inside the metal parts and to check for ancient writing on the machine.
According to their research, the researchers believed that this machine could have been used to compute eclipses of the sun and moon and was also able to show the movements of planets. A user could pick a day in the future and, work out a planet’s position on that date by moving some sort of crank (曲柄) on the machine.
Besides, the researchers discovered that the machine had at least 30 bronze gears (齿轮) with as many as 225 teeth, likely all cut by hand.
With all the collected information, the researchers came up with a new model for how the machine operated. The model has 29 of the 30 known gears and five more that were probably there but never found. Also，the new picture adds a previously undiscovered spiral dial (螺旋刻度盘) to the back of the machine near the bottom. A hand moving around the dial could have pointed to eclipses over a period of 18 years.
71. The passage is most probably taken from _____.
A. a short-story collection
B. a popular science magazine
C. a political report
D. an old personal diary
72. What is the passage mainly about?
A. New research on calculating the positions of planets.
B. A popular way of computing eclipses of the sun and moon.
C. Scientists’ interest in the secrets of a 2,000-year-old Greek shipwreck.
D. A mysterious machine which could be used for astronomical research.
73. What do we learn from the third paragraph of the passage?
A. The machine might have been used to calculate the positions of the planets.
B. Scientists made great progress in predicting eclipses of the sun and moon.
C. The researchers discovered some secrets in the Greek shipwreck.
D. The machine can be of great help for people working out the sizes of planets.
74. The researchers made a new model because they____.
A. wished to repair the broken machine
B. wanted to study the shipwreck more conveniently
C. hoped to know how the machine worked
D. expected it to be used in modern scientific research
75. Which of the following statements is TRUE about the old machine?
A. It has 35 gears on it.
B. It has a spiral dial.
C. It was invented about 100 years ago.
D. Its gears have many teeth.

A mysterious machine found in a 2,000-year-old Greek shipwreck may have been used to calculate the positions of planets, predict when eclipses (日、月蚀) were to occur, and study other parts of astronomy (天文学). When it was found underwater about 100 years ago, the machine was in poor shape. Its metal pieces had become one mass (堆), and then broke into pieces.

When the researchers began to study what was left of the machine, they thought it might have something to do with astronomy. To find out more, they recently used advanced imaging methods, including X-ray computer tomography (断层摄影术), to look inside the metal parts and to check for ancient writing on the machine.

According to their research, the researchers believed that this machine could have been used to compute eclipses of the sun and moon and was also able to show the movements of planets. A user could pick a day in the future and, work out a planet’s position on that date by moving some sort of crank (曲柄) on the machine.

Besides, the researchers discovered that the machine had at least 30 bronze gears (齿轮) with as many as 225 teeth, likely all cut by hand.

With all the collected information, the researchers came up with a new model for how the machine operated. The model has 29 of the 30 known gears and five more that were probably there but never found. Also，the new picture adds a previously undiscovered spiral dial (螺旋刻度盘) to the back of the machine near the bottom. A hand moving around the dial could have pointed to eclipses over a period of 18 years.

71. The passage is most probably taken from _____.

A. a short-story collection

B. a popular science magazine

C. a political report

D. an old personal diary

72. What is the passage mainly about?

A. New research on calculating the positions of planets.

B. A popular way of computing eclipses of the sun and moon.

C. Scientists’ interest in the secrets of a 2,000-year-old Greek shipwreck.

D. A mysterious machine which could be used for astronomical research.

73. What do we learn from the third paragraph of the passage?

A. The machine might have been used to calculate the positions of the planets.

B. Scientists made great progress in predicting eclipses of the sun and moon.

C. The researchers discovered some secrets in the Greek shipwreck.

D. The machine can be of great help for people working out the sizes of planets.

74. The researchers made a new model because they____.

A. wished to repair the broken machine

B. wanted to study the shipwreck more conveniently

C. hoped to know how the machine worked

D. expected it to be used in modern scientific research

75. Which of the following statements is TRUE about the old machine?

A. It has 35 gears on it.

B. It has a spiral dial.

C. It was invented about 100 years ago.

D. Its gears have many teeth.

The earth’s most rich resource—water has become one of the most precious resources in the United States as rivers, lakes, and freshwater reservoirs are increasingly exploited for human use. Consequently, using precise farming techniques to refine “irrigation scheduling” is a research area of particular interest to Susan Moran, a researcher with the US department of Agriculture. She explains that in the southwest, irrigation is both difficult and expensive. There, she says, farmers have a tendency to over irrigate, spending both more time and money than is necessary.

“I’m trying to provide new information that could be used by farmers to schedule irrigations to improve their profitability and use less water,” Moran says. “Farmers often look at weather changes and then schedule irrigation based on that information. But if they had better information, they could use scientific models to compute more precisely how much water their crop is using. ”

Rather than guessing their crop’s potential need for water based upon weather changes, farmers can use remote sensors to measure how much water their crop is actually using. This would give them a more accurate measure of how much more water it needs.

Moran believes that if farmers are getting good and timely measurements of plant and air temperature, then they can program when and how much water to give each crop through an irrigation system. No more water would be used than needed, thus saving cost and conserving water.

Moran introduces one study she conducted in Arizona to investigate the use of remote sensing data for scheduling cotton irrigations. Typically, those farmers irrigate ten times per growing season, but evidence showed that some of those farmers could achieve basically the same harvest with only nine irrigations.

“In those cases, one less irrigation saved more than all the cost of remote sensing data,” she states. “Both irrigation and satellite remote sensing data are expensive. But then again many farmers are used to wording together as a group. They are used to sharing. I’m hoping they could do the same with remote sensing data—purchase one scene over a large area to cover many farms, which would further reduce the cost. ”

46. What does Moran think is the problem with farmers?

A. Over-used reservoirs. B. Precision farming.

C. Irrigation researches. D. Over-irrigation.

47. How can farmers get the new information about their crop?

A. To reschedule irrigation as required.

B. To watch weather changes regularly.

C. To use remote sensors as researchers suggest.

D. To use scientific models since computing is more reliable.

48. What do farmers check upon when they decide how much water each crop needs?

A. Profitability. B. Remote sensors. C. The cost. D. Air temperature.

49. What’s the purpose of Moran introducing the study she carried out in Arizona?

A. To investigate the use of remote sensing data.

B. To support her viewpoint in the previous paragraph.

C. To show how farmers can reap a harvest.

D. To criticize those farmers who used too much water.

50. What is among the best possible ways to help save farmers’ money?

A. Changing irrigation. B. Sharing sensing data.

C. Buying one computer. D. Extending the farms.