system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: When should I use _or vs _er?

For example, "bisectOR" vs "teachER". Is there a rule?
gpt
-or is for words with Latin origins, -er is for the rest.

I don't think there is an easier way for telling which to use, a quick google search results in a rather hit-or-miss rule of thumb where nouns which can end in -ion (profession, education) end with -or.