Legal is used to describe things that relate to the law.
He vowed to take legal action.
他发誓要诉诸法律行动。
the British legal system.
不列颠法律体系。
I sought legal advice on this.
我就此事寻求了法律咨询。
An action or situation that is legal is allowed or required by law.
What I did was perfectly legal.
我做的事情完全合法。
drivers who have more than the legal limit of alcohol.
饮酒超过合法限量的驾驶员们。