At its most basic level, a roller coaster is a machine that USES gravity to send a train along a winding track.

从最基本的层面来说，过山车是一种利用重力让车体沿着弯曲轨道运行的机器。

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Roller coasters have three basic parts – thetrack, the train, and a motor.

过山车有三个基本部分——轨道、车体和动力设备。

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Located at Six Flags Discovery Kingdom in California, this roller coaster gives riders a sudden scare by stopping the train in mid-air.

加州六旗主题公园的垂直过山车，能在半空中突然停住，要多惊险有多惊险！

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Walt Disney Imagineer Chris Beatty talks about the magic mirror and the new Seven Dwarfs Mine Train roller coaster, which opens in 2014, in this exclusive video interview.

FORBES: Connect

It takes nine months to train a new roller to make only a small cigar.

ECONOMIST: Cuban cigars