To excuse oneself before there is occasion is to accuse oneself. To draw blood in full health gives the hint to ill will. An excuse unexpected arouses suspicion from its slumbers.

在有必要辩解之前就为自己辩解，其实就是在控告自己。在完全健康的时候放血，就等于暗示自己有病。一次意料之外的申辩，会唤醒原本沉睡的怀疑。

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So the filmmakers focused on the theme of defining oneself in the face of unexpected obstacles.

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