知识点一：The multifaceted nature of language
III. The definition of language
'Language is a purely human and non-instinctive method of communicating ideas, emotions and desires by means of voluntarily produced symbols.' (Sapir, 1921)
“Language is 'the institution whereby humans communicate and interact with each other by means of habitually used oral-auditory arbitrary symbols.' (Hall. 1968)
'From now on I will consider language to be a set (finite or infinite) of sentences, each finite in length and constructed out of a finite set of elements.' (Chomsky, 1957)
教师解析：
Each of these definitions pinpoints some aspects of the essence of language. Chomsky defines language by pointing out its connotation, while Spair’s definition focuses on its function.
To sum up, the above definition captures some important aspects of language. What characteristics of language do you think should be included in a good, comprehensive definition of language?
