tie one down

One officer had to tie down the left leg, another one the right leg, and so on, but I was the only one to execute the condemned.

一个人负责绑住左腿，另一个人负责右腿，以此类推，但我是惟一负责处决死刑犯的人。

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The output can be more specific than just specifying the analog pin number, but the generic number allows flexibility because it does not tie down any one pin to any one job.

输出也可能比仅指定模拟管脚编号更为具体，但是本机编号灵活性更好，因为它不会将任何一个管脚束缚到某一项作业上。

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