Human brain is exceptionally complex and simple at the same time. Its extremely composite biological structure results itself in human everyday behavior that many people might consider rather simple than complex. In our research we will concentrate on the ways how a human brain can processes English and other human natural languages because taken in general sense the ability to speak English or other human languages is only serious distinguishing feature that rises humans over the rest of the world making a human an intellectual being. On the purpose of our research we consider natural language as naturally formed symbolic system completely independent of these symbols' physical nature that is a little more general than a common natural language definition. The principles of natural language processing in human brain are most important for us if we want to build equally powerful artificial general intelligence. We start with the features of human brain neurons and neural networks, and step by step create a computer model of human brain networks that is able to process and generate a reasonable speech. We can't give a detailed explanation of human brain functionality in this short article. Moreover, it is not our goal, and such research is not complete yet. The main result of our research is revealing the principles how tiny single neurons working together can produce intellectual-like behaviour that exhibits itself in proper speech comprehension and generation in accordance with current context.