他们只是在做为防止植被遭大规模破坏而必须做的事情。

They are only doing what is necessary to prevent wholesale destruction of vegetation.

《柯林斯英汉双解大词典》

汤姆暗示了他有事情要处理，必须做的事情，而且时间在飞逝。

Tom hinted at things he had to attend to; things that must be done; and time was fleeting.

youdao

在工作中，人们很清楚他们应该做什么：工作，赚钱，为了获得收入而做他们必须做的事情。

At work, people pretty much know what they're supposed to be doing: working, making money, doing the tasks they have to do in order to draw an income.

youdao

So, part of what goes on when you learn, is you have to learn the language --the phonemes that your language has.

因此你在学习语言时要做的一件事情便是,你必须学习你所学语言的各种音位

耶鲁公开课 - 心理学导论课程节选

and I just want to be at home, not having to do whatever I have to do,

并且我只想呆在家，不用做那些我必须做的事情，

去溜冰场 - SpeakingMax英语口语达人

But,in those days in high school-- but anyway, there we go--you'd go and do these things, and it would be a big sort of public spectacle,a spectacle.

不过那时候的高中--无论如何,就是那样--你必须去做这样的事情,那是个大型的公共活动

耶鲁公开课 - 1871年后的法国课程节选