Sharp blade key: hand must keep horizontal motion, force must be uniform and owner. on back must be straight or round straight, nearly edge department can not have a little hunchback.

刀刃锋利的关键所在：手必须保持水平运动，力必须均匀，刀背必须保持平直或圆直，近刃口部不得有一点驼背。

youdao

Once I was back down at the bottom, there was a very long, straight road. I imagined this is what it must feel like to be in prison.

等我回到山脚下，紧接着是一段长而直的路，我想像蹲大牢的滋味一定就是这样了。

youdao

There must be interest in him because he hasn't come back straight away and said 'yes'.

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