Susan’s answer to “Every teacher of English that has taught me always advises to "write what you know". Do you believ…” > Likes and Comments

I don't like when they DON'T write what they know, especially if it's something I know isn't right but it comes across as preaching to the world.
I won't read writers who do that.

If you REALLY understand Write What You Know, you will understand that you can know something in multiple ways, not just your own personal face-to-face experience. For example, Susan Wittig Albert came to KNOW Eleanor Roosevelt and Lorena Hicock through her extensive research, just as she researched Beatrix Potter before and during the writing of that series. So, Vicki G, don't be too quick to dismiss something just because the author can't present a first-hand, eyes-on account of the environment and people about which s/he writes.

I agree. Write what you are eager to learn. An English teacher.

Every teacher of English should have taught you to use "who" instead of "that" for a person.