If you don't know good English, you can't explain your expression in the in the right way. So besides creating good content, you must practice learning English. For a quality post, you have to write something that would be useful to others and not be considered spam at all. For that, you should know good English if you are going to write it on an English board. A post would be quality if you didn't know English but wrote on your local board in your native language as well. Criteria for a quality post should be in a useful manner.
Since majority here are using English language, the fact that you want to impress them with your own quality post, then you should conform to their language standard, and obviously that’s English. Hence, you have to learn using English seriously so that you can attract the attention of majority, and once they notice and appreciate your post, then it’s easier for them to merit your post.On the other hand, sticking to your own local language may not actually be a problem as long as you consistently earn merits from your posts. But if you seldom earn merits, then you should learn to go out from your comfort zone and embrace using English in your post. That could only be hard at first, but eventually you will get used to it if you consistently make use of it, and learn to observe as well from others how they manage their posts with English language.
