Well forum posts should have a set of rules, something that would go like this:
1. Do not mindlessly spam, make your posts worth-while to read.
2. Forum language is English and if you post in some other language, add a translation, so others could understand it.
3. A post should be at-least 1 sentence or 5-7 words min.
4. Don't flame on the forums and keep your other, more subtle insults to yourself as well.
5. Do NOT double-; triple-; or quadruple-post. It looks stupid and makes you look like a post-whore. use the ''Edit'' function.
6. Write your posts in the BEST English you can pull off.
7. Don't use color combinations for text that make others wanna jab their eyes out.
You could freely add/remove rules from here, this is just a suggestion.