Made of super strength high speed steel with 4 precisely ground edges make it an efficient, accurate and long lasting tool for mortising.

由高强度高速钢精工制造而成，带有四个精确磨削的切削刃，使得该产品成为高效率，高精度，长寿命的开榫工具。

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On the top of each was a hole, the edges of which were defined with twisted logs, set flush into the ground, like wooden lips.

在每一个土堆顶上都有一个洞，旁边都用一些被弯曲的木头围住，水就经过那个流在地上，这些木头就好像木嘴唇一样。

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If a train had gone over it the edges would have been ground down, but as you can see in the picture the edges are sharp.

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Rain rippled the surface of a reflecting pool at the ground zero memorial, where people placed flowers along the edges.

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