首先，着火后火焰是沿着点火前的可燃区域迅速蔓延的。

The first, after ignited, the flame spreaded along the flammable zone before igniting.

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图片上是这件化学分析及摄像仪器在新墨西哥州洛斯阿拉莫斯国家实验室进行点火测试前拍摄的。

The Chemistry and Camera instrument, seen above before a recent test firing at Los Alamos National Lab in New Mexico, USES a pulsed laser beam to vaporize a pinhead-size piece of material.

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或者遇到事发前点火的那个男孩。

Or else find the boy who lit the fire in the first place.

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