Upper and lower piston rings are arranged inside a piston gaseous ring groove, and openings on the two-piece piston rings are mutually staggered.

在一个活塞气环槽内设有上下二片活塞环，二片活塞环上的开口相互错开。

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With his 20-power telescope and with his eyes in bad shape he might have mistaken Saturn's gaseous ring to surmise that it was formed of one planet with two moons as satellites.

由于伽利略用的是20倍的望远镜，而且他眼睛的状况也很糟糕，他很可能把土星的气环搞错了，并因此得出结论-土星是由一个行星和两个卫星组成的。

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Current theories suggest two ways in which a gaseous, dusty ring around a young star can form into gas-giant planets.

现有的理论提出了两条途径来解释在一个由气体尘埃环围绕的年轻恒星周围如何形成气体巨型行星。

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