This is a hard rule to follow.

这个规则看来很难遵守。

youdao

This isn't a hard rule.

这不是一个硬性的规则。

youdao

No hard rule dictates how long a line of code should be.

没有硬性规定一个代码行应该多长。

youdao

Whether or not you find the no branching rule hard to believe, if both views are stuck with it,well,then we're stuck with it.

无论你是否觉得无分支规则很难接受，这两种观点都卡在这里了，我们也就卡在这了。

耶鲁公开课 - 死亡课程节选

Though there is no hard rule that committee chairmen allow minority-view witnesses to testify, it does happen.

CENTERFORSECURITYPOLICY: Radicalization lessons

In retrospect, you know, I thought it was such a hard rule because it took me a long time to find a buyer, but it worked out because they didn't have trouble qualifying for a loan.

NPR: Tips on Considering a Condo Purchase

Given the new king's lesser experience and stature, he will find it hard to rule in such a hands-on manner.

ECONOMIST: Jordan��s new king