Is there anything you require, sir?先生, 您有什么需要吗？

Assistance will be provided, if required.如有需要, 可提供帮助。

The job requires a sound knowledge of classical music.这项工作要求掌握扎实的古典音乐知识。

a career that requires many sacrifices of those who pursue it需要从事者作出许多牺牲的一份职业

I require you follow the guidelines I lay out below.我要求你遵照我在下面列的原则。

The rules require you to inform us of any change in your circumstances.这些规定要求你遇到情况有任何变动时都要告知我们。