Until then, Siemens 10000 thyristor valves. [ ] A．producedB．has been producing C．has producedD．had produced 题目和参考答案——青夏教育精英家教网—

题目内容

Until then, Siemens ________ 10000 thyristor valves.

[　　]

A．produced

B．has been producing

C．has produced

D．had produced

答案：C
解析：

Until then后用现在完成时，所以选C。

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It was not until then that I came to know knowledge ____ only from practice.

　 A. had come 　 B. came C. would come 　 D. comes

MOSCOW(Reuters) – Russia hopes the United States will extend the deadline to retire its space shuttles beyond 2011 and has heard unofficially it is possible, the head of Russia"s space agency was quoted as saying on Friday.

The U.S. space agency NASA(美国宇航局) plans six more missions by its fleet of aging space shuttles by late next year or early 2011 after the construction of the $100 billion International Space Station (ISS) is completed. The shuttles will then be retired. But the head of Roscosmos, Russia"s space agency, said he would prefer to see further shuttle missions to the Space Station, now in orbit 360 km (225 miles) above Earth. "From some sources we have learned that it is possible to extend the life of the shuttle beyond 2011," Roscosmos chief Anatoly Perminov was quoted by RIA news agency as saying. Reuters was not invited to the briefing(简报会). "Then the situation would change substantially and it would be possible to work jointly with the Americans, unlike now, when the main burden (for the ISS) lies with the Russian side," Perminov was quoted as saying by Interfax. Perminov said he had not been told this through official channels, Interfax news agency reported. He added that NASA"s new chief and former astronaut Charles Bolden would visit Russia"s Baikonur cosmodrome on September 30 in his first foreign trip.

NASA"s future strategy is currently under review with the main focus on possible flights to Mars. It is also encouraging a private space taxi project to the ISS. NASA"s current plan, conceived under former President George Bush after the Columbia accident, is to complete the space station, retire the shuttles and build new spaceships. A new rocket and capsule to transport astronauts to the ISS is also being developed but will not be operational until about 2015. Until then, NASA will rely on Roscosmos and must pay $50 million per seat for flights to the ISS by Soyuz capsules.

The U.S., Russian and Chinese governments are the only entities currently capable of human orbital space flight, although several U.S. companies are developing vehicles and support services to do so.

What does the underlined word “this” in Paragraph 2 refer to?

A．NASA agrees to extend the life of the shuttles beyond 2011.

B．Reuters was not invited to the briefing.

C．The US would work jointly with Russia.

D．NASA’s new chief would visit Russia’s Baikonur cosmodrome.

NASA’s current plan includes all the following EXCEPT .

A．completing International Space Station

B．flights to Mars

C．retiring the current space shuttles

D．building new spaceships

If the US doesn’t extend the life of the shuttles beyond 2011, .

A．International Space Station will be quit

B．Roscosmos will have to build more spaceships

C．NASA will have to quicken the development of the new rocket and capsule

D．Roscosmos will be burdened with the transportation to ISS

We can infer from the passage that .

A．China has already been involved in the project of flights to Mars

B．it is certain the NASA will retire the current space shuttles as planned

C．NASA is considering Russia’s suggestion

D．NASA will be able to provide a private space taxi project to the ISS by 2015.

The West began to take more notice of the East.The fifth volume of an enormous work reassessing the Chinese contribution to science and technology is to be published next year.The first volume,which was published twenty years ago,set the tone for the whole work.In it,evidence was given to show that many inventions which,until then,western historians had claimed forEurope,were made first in China.The attempt to rewrite the intellectual history of the world was not received without protest by some reputable historians.However,the evidence that has been presented so far in the first four volumes has persuaded many historians who were skeptical at first.China’s invention of paper,printing,the magnetic compass and gunpowder has never been disputed,but this new history has added advanced bridge design,mechanical clocks,paddle boats and many other inventions to the list.

In the four volumes published so far no attempt has been made to explain why China has not kept up with the West in science and technology in modern times.It is probable that the answer is to be found in the social and economic history of China,where a static(稳定的) society under a relatively kind regime(政权) of scholar-gentry(贵族) contrasts with the potentially revolutionary and dynamic(有活力的) society of the West at the end of the Middle Ages.In recent years,the Chinese government has been making every effort to catch up with the West again,and there is little doubt that the gap is being reduced year by year.But will China avoid the West’s mistakes?

The first volume was published__________.

A.ten years ago B.last year C.five years ago D.twenty years ago

In Line 7,the word “skeptical” means _________.

A.doubtful B.worried C.sad D.angry

Which of the following is not mentioned in the passage?

A.Gunpowder. B.Needle. C.Paddle boats. D.Bridge design.

The best title for this passage is _________.

A.China’s Inventions

B.Comparisons Between the East and the West

C.China Is Catching Up

D.Situations in China

It was not until then that I came to know that knowledge _______ only from practice.?