Well, a sledge sliding on flat ice.

我们再来看下雪橇在光滑冰面上滑行的例子。

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So remember the sledge moving over the flat ice.

还记得雪橇在平滑冰面上的滑行么。

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So its very smooth very flat ice and you push a sledge on it and then you let go, what happens? The sledge keeps going. How can that be?

冰面很光滑，你推动雪橇，然后放手，接下来会怎样呢，雪橇仍然会继续前进，为什么会这样呢？

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The water that drains away creates an instant skating rink, a moat of flat ice.

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As Devils forwards Jacob Josefson and David Clarkson screened Rangers goaltender Henrik Lundqvist, Salvador flicked a soft wrist shot that skipped along the ice like a flat rock across a pond and through Lundqvist's legs.

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The ice moves a few metres a year but it is quite flat.

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