On the pages of this small book converge, perhaps, the most difficult problems of modern linguistics - the problem of language and speech and the problem of sentence. The meeting of these problems is not accidental and is not episodic; their paths have already crossed many times, sometimes went in parallel, but never reached any satisfactory and unambiguous solution. Whenever a fairly large-scale linguistic theory appeared or a new method of analyzing and describing language was created, linguists, in full force of new scientific means and techniques, invariably returned to these problems ? at least since the time when these problems arose.