It worked contrariwise—first you dialled the number, then you put the money in.

这部电话的操作方式相反，即先拨通号码，然后投入钱币。

《牛津词典》

First you have to have fun.

首先，你必须玩得开心。

youdao

If at first you don't succeed, try, try again.

一次不成功就反复尝试。

《牛津词典》

You can make your own chances. But first you have to know what you are after,my dear."

VOA: special.2009.02.14

So on the one hand--temporal sequence-- first you know Ruth, you meet Ruth, you get to know Ruth.

所以一方面,按时间顺序来说,你需要先知道露丝,见到露丝 了解露丝

耶鲁公开课 - 死亡课程节选

In the first example, you could be at a social gathering and you really feel the need for some nicotine.

在第一个例子中，你可能在一个社交聚会上，你特别想找个地方抽根烟。

Do you mind 课堂 - SpeakingMax英语口语达人

First you have to be self-aware, and decide on what you want to be a habit.

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First you need to serve your apprenticeship under the supervision of a licensed broker.

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The way I see it, first you put out the fire and then you worry about what caused it.

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