Although the word linguist is sometimes used to refer to a person who speaks several languages, the modern scientific linguist is not particularly interested in actually using languages for communica- tion.
A scientific linguist is not necessarily a polyglot b ut may,
in fact, speak only the native tongue. Since the linguist is interested in describing the syntax and meanings of a language, as well as the sounds and principles of word formation
it is often necessary to concentrate on either the native language or, if possible, on some other language that is equally weil known.
The result is that much American research during lie past two decades has heern devoted to English, although languages as diverse as Japanese, Turkish, Swahili, and the languages of westen Europe have also been investigated in great detail. nguage and speech are not synonyrns. Speech is a con- cte, physical act--the production of specific utterances contain ing particular words arranged in particular ways and expressed by niean s of certain sounds.
Language is a mental phenomenon, a body of knowledge about sounds, meanings, and syntax which resides in the mind. This knowledge can be put to use, of course but the speech,
or writing, that results is merely a representation oi the lnguage-it is not the language itself. Linguists are con