Perfection comes out of molds or off assembly lines. Things made by nature or by hand are imperfect.

完美常常来自于模型或是装配线，大自然或手工制造的物品往往是不完美的。

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General Motors says it will lay off nearly 50,000 employees this year and that it plans to close five assembly plants, eliminate thousands of dealerships and reduce the number of its brands from eight to four - all in an effort to stay afloat.

VOA: standard.2009.03.30

Various designs of electric cars are already rolling off assembly lines and are expected to become widely available in 2012.

FORBES: Magazine Article

So what was just an idea two decades ago is now rolling off assembly lines in cutting-edge fuel efficient cars that you can plug in at night.

WHITEHOUSE: President Obama Speaks on American Energy

They have been rolling off assembly lines in unprecedented numbers since the country's accession to the WTO pushed down prices of imports and so helped to stimulate the market as a whole.

ECONOMIST: On a roll