You only get one first impression.

你只有一次机会给别人留下第一印象。

youdao

You only get one shot, do not miss your chance to blow.

你只有这一次机会，不要错过引爆众人的机会。

youdao

Your pick, left or right, but you only get one and it's black.

由你做主，左手手套或是右手手套，但你只能得到一只，而且是黑色的。

youdao

And homework, it varies between classes. Sometimes you only get one assignment,

家庭作业，也跟课程的不同而有所差异。
有时候你只有一个作业，

很好奇住宿生活 - SpeakingMax英语口语达人

If you're a dealer, you've got to keep your bid-ask at market; otherwise, you'll get only one side or the other, right?

如果你是中间商,你的出价必须与市场一致,否则就只能拆东补西

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Now, what happens is half of the participants in the experiment who have listened to each of these tapes-- You only get to listen to one tape.

这时，发生了一件事儿,他们要求半数的受访者,听过这些磁带的人-,只能听磁带。

耶鲁公开课 - 心理学导论课程节选

"If we put our brand on stuff, sometimes you only get one chance, " LaSorda admits.

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"Some things are tied into the narrative and you only get one base, " he said.

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That perception is your reality, and you only get one chance to make it a good one.

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