Similar machines have flown in space aboard NASA's shuttles, but they couldn't be tested for long enough to prove whether they were effective.

类似的机器也曾搭乘美国宇航局的航天飞机在太空中飞行，但无法进行时间足够长的测试来证明它们是否有效。

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The Long march is a march that tests truth. Truth must be tested in practice and can only be established in practice.

长征是一次检验真理的伟大远征。真理只有在实践中才能得到检验，真理只有在实践中才能得到确立。

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The 56-meter-long jet will be tested at five airports, including Osaka’s Kansai and Hiroshima during its six-day itinerary in Japan, according to news reports.

据新闻报道，在日本为期6天的行程中，这架长达56米的喷气式飞机将分别在5个机场进行试飞，包括大阪的关西国际机场和广岛机场。

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This is where the long-term viability of Windows as a mass market mobile OS will be tested in the coming summer.

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Now that the Stalinist hermit-state has successfully tested long-range missiles and atomic weapons, though, such statements have to be taken seriously.

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