我们学校必须遵守的规定是：没有家长的书面允许不能给孩子做测试。

One unbreakable rule in our school is that no child can be tested without written parental permission.

《柯林斯英汉双解大词典》

这是各行各业的人都必须遵守的一条规则。

This is a rule that people from all walks of life must follow.

youdao

我想我会给他们一个必须遵守的最后期限。

I think I'll give them a deadline and hold them to it.

youdao

There is a plurality of solutions that conform to the boundary conditions, which is that the system must be bound.

这有许多解决方式,来遵守这个有界条件，那个系统必须是有界的。

麻省理工公开课 - 固态化学导论课程节选

..That's just as good as the land that you took, so... That's true. Locke says there has to be this right to private property in the earth is subject to the provision that there be as much and as good left for others. What's your name?

而且是跟你占有的土地一样好的。,的确如此，洛克说过,土地私人所有必须遵守的是,还有足够多足够好的土地留给别人，你叫什么？

耶鲁公开课 - 公正课程节选