长期以来，射孔被认为是钻井工程的最后一道简单工序。
For a long time, perforation is Just regarded as the last simple process in drilling.
制造这种喇叭非常简单：塑料被融化制成模型然后安装，一群妇女磨平锋利的边缘，工序完成。
Making the trumpets is simple: plastic is melted into a mold and then it sets.A small group of women take off the sharp edges to finish off the process.
制造这种喇叭非常简单：塑料被融化制成模型然后安装，一群妇女磨平锋利的边缘，工序完成。
Making the trumpets is simple: plastic is melted into a mold and then it sets. A small group of women take off the sharp edges to finish off the process.
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