倘使你一定要知道的话，这是我男朋友给的。

It's from my boyfriend, if you must know.

《牛津词典》

这把她的魂都吓飞了，如果你一定要知道的话。而且我也被吓坏了。

It scared the hell out of her, if you must know. And me, too.

《柯林斯英汉双解大词典》

你一定要知道这个欺负者的限度。

You must know the extent of the bully's limits.

youdao

So, that is a tricky problem to begin with because if you take this formula here, it tells you y if you know t, but no, we're not saying that.

以这个问题刚开始的时候有点难度,因为如果你要用这个公式,求y的时候就一定要知道t,但是,我们不知道

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