题目内容：
根据内容，回答题。Neither the Americans nor the Russians havethe resources to continue human space flight on their own; both sides know they need eachother. 61 )It's much easier andcheaper to get used to each other and to blend differing operating styles,languages, and systems on the aged Mir (a Russian word for "peace" )than trying to do that while jointly building a new space station. NASA, in fact, calls itsprogram of shuttle flights to Mir Phase 1 of the International Space Station(ISS). Phase 2 marks the beginning ofactual construction. The procedures usedto dock the shuttle to Mir, for example, also will be used as a lifeboat forthe ISS. And Progress freighters, likethe one that crashed into Mir in June, will haul cargo to the ISS. 62)One unintended benefit of Mir'stechnical troubles is that they have actually forced the two nations to workmuch more closely together than they had planned.
Except for a brief period in the 1970s withSkylab, NASA has never operated a space station;the Russians have been running them foryears. Astronauts have long been trainedintensively to perform specific tasks on shuttle flights lasting 18 days orless. 63)Russian astronauts, however,learn more general skills, since they spend many months in orbit and no one canforecast all the problems they might encounter. As a result of shuttle-Mir experience, NASA isrevising astronaut training to include more of the general skills they willneed on the ISS
NASA decided to send astronauts to Mir based on its long record of safeoperation. But this year, crews aboardMir have faced two of the most serious emergencies in the history of human spaceflight. 64) In February, an oxygengenerator caught fire , shooting out 4-foot-long jets of flame like; fireextinguishers were bolted in place, delaying reaction to the fire. In June, a Progress Freighter collided withthe Spektr module, puncturing it. Spektrhad to be sealed off to prevent all the air from leaking from the spacecraft. 65 ) The ancient computer that controls Mirhas failed many times , causing most other systems, including the one thatkeeps the station's solar panels pointed at the sun, to shut down. One failure in August occurred while aProgress was docking. Last week, the computercrashed again, the carbon dioxide removal system shut down, and a mysteriousbrown fluid-probably rocket fuel——appeared to leak from the station.
__________
参考答案：
答案解析：