A triangle is a basic drawing operation on which you can build more abstract operations.

三角形是基本的绘图操作，在此基础上可建立更为抽象的操作。

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Basic operation skill for Surface Grinder, Milling Machine and Lathe, Knowledge in basic engineering drawing and basic mold tooling concept.

能操作熟悉平面磨床，手动铣床，车床等设备，能看懂基本的工程图纸，具备基本的模具概念。

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Drawing used to make final decision with basic mould messages such as structure, operation, main dimension, special requirements and so on.

具备模具结构、运作、主要尺寸、特别要求等，定案会议用图纸。

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