Ask the diver to purse the lips. Look carefully to see that both sides of the face have the same expression.

让潜水员缩起小嘴唇，仔细观察脸部两边的表情是否一致！

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The surface of both sides has beautiful ripples and, when you look closely, you can see that these are the scars from its making, where the flakes of the flint have been carefully chipped off.

细细观察下来，就可以看出那是打磨过程中留下来的。 当年工匠精工细磨，慢慢地在这燧石片上敲下片片碎石，就留下了道道的痕迹。

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