We use language every day. We live in a world of words. Hardly anymoment passes with someone talking, writing or reading. Indeed, __1__languages is most essential to mankind. Our lives increasingly dependon fast and successful use of language. Strangely enough, we know __2__more about things around us than on ourselves. For example, language __3__is species specific, that is, it is language that differs human from __4__animals. However, we do not know yet how exactly we inquire language __5__and how it is possible for us to perceive through language; nor we __6__ understand precisely the combinations between language and thought, __7__language and logic, or language and culture; still less, how and when language started. One reason for this inadequate knowledge of language is that we, like language users, take too many things for granted. __8__Language comes to every normal person so naturally that a few __9__of us stop to question what language is, much less do we feel the necessity to study it. Language is far more complex than most people have probably imagined and the necessity to study it is far greater than some people may have assured. Linguistic is a branch of science which __10__takes language as its object of investigation.