Hi. The rules are listed above (On my screen, it is under the big Teflnet Forums / TEFL teacher discussion and help, on the same line as the three horizontal bars and "Quick links" and "FAQ."
Basically, they say
use English; don't advertise; don't attack people; if you complain about a course or school, you must use your real name and give dates.
It doesn't say it, but obviously, content should be on-topic: Post in the correct forum.
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Moderator: Joe