The single most important thing that you can do as a student, an employee or as a professional of any sort is to use appropriate language in your written and verbal communication. In an academic or professional setting, it is crucial to always be putting your best self forward. This means taking care to make a great impression and portraying yourself as someone who is mature, competent, professional, and driven to success.
Regardless of the language you speak, you have grown up knowing the importance of using formal language in the situations that best warrant it. Those situations being the ones that either circle around a serious subject or event, or involve people that we do not know well.
It is difficult to silence what you know. As writers, we are cautious to write outside of our own perspectives and backgrounds, focusing instead only on the things that we have a deep understanding of. What we can do, however, is take care to avoid using derogatory terminology or making statement that reinforce specific negative stereotypes that belittle other classes of people.
As English speakers, when use indefinite pronouns whenever we are referring to people or objects without specifically stating who or what they are. Pronouns for people often end in body or one. Whereas pronouns for things will typically end in thing.