We are a good community because we can understand what others say, and we understand what others say only because we use a common language.
If we use different languages, we'll have some serious problems, for example, we'll have guys from Indian subcontinent speaking their own languages(you don't want to get messed up in Indian languages, trust me), we'll have a group of Latin players, a group of Arabic speakers, Turks, Philippinos! all will make their own small community in this forum.
Nobody cares if your English is not that good, it's not your mother tongue anyways (probably)! (Lol I learned my bad englas by watching subtitled Hollywood movies XD...ps. phack english class in school)
Use your native language if you are really bad, but try speaking a common language.