This tooth is decayed. It must come out.

这颗牙齿龋蚀了，应当拔掉。

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But somehow we believe that if you destroy energy, it must come out in some other form, and you cannot create energy out of nothing.

但我们却相信，你若是损耗了动能，它肯定转化为某种形式，能量并非无中生有的。

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"If this road goes in, it must come out, " said the Scarecrow, "and as the Emerald City is at the other end of the road, we must go wherever it leads us.

“如果尽走着这条路，必定会跑出森林去的，”稻草人说，“如果翡翠城是在路的那一端，我们必须顺着这条道路所指引的地方走去。”

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