The prison governor has refused to let him go, saying he must first be given authority from his own superiors.

监狱长已拒绝释放他，说他必须首先得到上级的许可。

《柯林斯英汉双解大词典》

A person to help the weak, he must first become the strong.

一个人要帮助弱者，自己要首先成为强者。

youdao

Hence, before one can be a king, he must first be a victor.

因此，在人能作王以前，他必须先作得胜者。

youdao

But Wednesday,the U.S.Senate joined the House in refusing the president's request for $80 million to close Guantanamo, saying he must first come up with a concrete plan to deal with the remaining 240 detainees.

VOA: standard.2009.05.21

Of course, before doing so, he says, "you must call him first a tyrant."

当然，在叛乱或是弑君之前，你得确定你要诛杀的是一位暴君“

耶鲁公开课 - 政治哲学导论课程节选

He tells VOA tougher action must follow. "This is am important first step, but it is only a first step,"

VOA: standard.2009.12.09

To get there, he must first convince people of the value of sharing -- a task he acknowledges as tricky.

CNN: With new mobile apps, no one's a stranger

In any case, he must first regain his grip over the party at what is likely to be a rowdy gathering later this month.

ECONOMIST: Austria's collapsing government: Back to square one | The

If the President wants to use a story from the Torah to support his progressive political agenda, then he must first understand what the Torah means.

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