我们都必须努力互相帮助。

We must all try and help each other.

《牛津词典》

这是一件艰苦的工作，因此你必须努力去做。

It's a hard work, so you must work hard.

youdao

她必须努力表现自己以求得升迁机会。

She had to push herself forward to get a promotion.

《牛津词典》

Knowing what iambic pentameter is, is not a gift of birth, but rather something that comes through a little bit of practice, which means we have to work at it a little bit.

没有谁是生来就知道抑扬五音步格诗，是需要努力才能知道的，这说明我们必须在这个上面花点功夫。

耶鲁公开课 - 现代诗歌课程节选

So you have to try. That's the thing.

所以你必须努力。就是这样的。

就业很难 - SpeakingMax英语口语达人

And the context of sorting, the worst case is your handed a problem that's in complete reverse order because that implies you have - to do as more work that could possibly-- that you could-- you have to do more work than you would of course if things were in perfect order.

在排序的环境中，最糟糕的情况是待排序的序列是,完全逆序的，在这种情况下,你不得不做更多的工作-,比起一个较理想顺序的序列,你必须花费更多的努力。

哈佛公开课 - 计算机科学课程节选