Coach too should have a knowledge of first aid.

教练也要有紧急救护知识。

Have a knowledge of XML concepts and related technologies?

了解XML概念及相关技术。

Rescue workers should have a knowledge of ropes and knots and lashing.

救援工作者应具备关于绳索、打结和捆扎的知识。

To achieve this goal, one must have a knowledge of population genetics.

要达到这个目标，种群遗传学知识必不可少。

It is very necessary to have a knowledge of English in international trade.

在国际贸易中，具有一定的英语知识是十分必要的。