He says his department will conduct more testing on key personnel including managers, vendors and customers.

市场监管局将加强对市场管理者、经营者、进场交易者等重点人员的检测。

This included key personnel who had been involved from the very inception.

这包括从一开始就参与其中的关键人员。

The show has been hit by the departure of key personnel.

【key】由于主要演员离去，演出受到了影响。

Last but not least, when l am doing research, I might want to know some other information, such as historical background and the introduction to key personnel.

最后但并非最不重要的一点是， 当我进行研究时，我可能想了解一些其他信息，例如历史背景和关键人员的介绍。