The rocket is long and slender, and fatter on top because its second stage is thicker than its solid rocket motor-powered first stage.

火箭又长又细，上部有点粗，因为它的第二级比固体燃料火箭发动机驱动的第一级要厚。

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The first stage of the two-stage Naro rocket was designed and built by Russia and the second by South Korea.

“罗老”号二级火箭的第一级由俄罗斯设计并建造，第二级由韩国负责。

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After the first stage burns out it falls back to earth along a parabolic path while the engines of the second stage fire to thrust the rocket into an earth orbit.

当第一级烧毁后，沿抛物线的轨道落到地球，而第二级的发动机点火把火箭发射到地球轨道。

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Those worries assume that all of the rocket's nine first-stage engines, as well as its second stage, will burn and shut off on cue.

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