I'm not implying that you are autistic or have some form of social disorder, but you definitely type like you do. You need to understand that part of communicating ideas with people is understanding the situation and context behind the conversation. You can be formal when speaking to an interviewer or at a science convention or something, but when speaking casually with people on a forum, you should type as if you're talking to a close friend. If you fail to understand that difference you will come off as either extremely ignorant or self-righteous.
The quality of text isn't determined by the vocabulary, but by how well it flows and how clear you are at communicating your idea. If you have something to say, say it in the simplest way possible for the sake of your readers.