他用了这样一个例子：木匠通常是怎么知道在什么情况下用直钉，什么情况下用螺钉的。

He gives the example of how a carpenter will often know that a nail works better in certain situations and screw better in others.

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漳州金宾利五金制品有限公司专业生产码钉、直钉、封箱钉、铝卡扣、订书钉等各种工业钉。

Zhangzhou KBL Hardware Co. , Ltd specializing in the production of various kinds of industrial nail. Such as: Yard nails, Straight nails, Carton sealer nails, Staples, U shape AL.

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甚至那些连一枚钉子都钉不直的男人都被认为是天生的电工、木匠、水管工和机械师。

Even men who can hardly drive a nail in straight are supposed to be born electricians, carpenters, plumbers and mechanics.

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