He was through with sports, not because he had to be but because he wanted it that way.

他放弃体育运动了，不是因为他非放弃不可，而是因为他想要那样。

《柯林斯英汉双解大词典》

I'm not sure what I want to be but I'm sure that you have already known.

我不确定我想成为什么，但我相信你已经知道了。

youdao

There can be but one room below, for there is but one chimney.

下面只能有一个房间，因为只有一个烟囱。

youdao

Or,if thou wilt not, be but sworn my love, And I'll no longer be a Capulet."

VOA: special.2010.01.06

Deny thy father and refuse they name, or if thou wilt not, be but sworn, my love, and I'll no longer be a Capulet." She's a Capulet.

否认你的父亲，抛弃你的姓名吧，也许你不愿意这样做，只要你宣誓做我的爱人，我也不愿再姓凯普莱特了，她姓凯普莱特。

麻省理工公开课 - 固态化学导论课程节选

So things can be dangerous. But generally, if you're smart, I think it's a very safe place to live.

因此，危险还是存在的。但大多数情况下，只要你精明点，我认为那儿还是一个非常安全的居住地。

在上西区 - SpeakingMax英语口语达人

If these burdens of proof are applied, there can inevitably be but one very fortunate ruling.

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Sirtuins will, he says, probably be but a small part of a more complicated picture.

ECONOMIST: How to live longer��maybe

Anyone you might have been journeying with will now be but a distant memory.

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