This explains the rules under which the library operates.

He ruled for eight months.

他统治了8个月的时间。

to follow/obey/observe the rules

遵循 / 服从 / 遵守规则

An important rule is to drink plenty of water during any flight...

一条重要的原则就是每次坐飞机都要多喝水。

I go to bed early as a rule .

我一贯睡得早。

Without unwritten rules civilized life would be impossible.

没有不成文的规章，就不会有文明生活。

Cold winters here are the exception rather than the rule (= are rare) .

在这里，严寒的冬天并不多见。

It's against all rules and regulations .

这违背了所有的规章制度。

The Israeli court has not yet ruled on the case...

以色列法院尚未对此案作出裁决。

There are no hard and fast rules for planning healthy meals.

在安排健康饮食方面，没有什么一定之规。

A good rule of thumb is that a broker must generate sales of ten times his salary if his employer is to make a profit...

根据经验来看，如果雇主要获得利润，那么其代理商必须卖出相当于其工资10倍的销售额。

The court ruled that laws passed by the assembly remained valid...

法院裁定议会通过的法律仍然有效。

The first rule is to make eye contact with your interviewer.

首先是眼睛要直视面试官。

As a general rule vegetable oils are better for you than animal fats.

一般来说，植物油比动物脂肪对人较有好处。

Sikhs were expected to adhere strictly to the religious rules concerning appearance...

锡克教徒应当严格遵守该教对外表的规定。

to break a rule (= not follow it)

违反规定

...a thirty-two-page pamphlet explaining the rules of basketball...

说明篮球规则的32页的小册子

...according to the rules of quantum theory.

根据量子论的原理

For four centuries, he says, foreigners have ruled Angola...

他说，外来者统治安哥拉的时间已长达4个世纪。

...a ruled grid of horizontal and vertical lines.

由水平线和垂直线画成的格子

He makes it a rule never to borrow money.

他的规矩是从不向人借钱。