Another aspect of language variation to be emphasized is that it depends on a number of factors, those being time, place, circumstances of use, speaker’s social background and individual traits. Correspondingly, we can speak about a number of variation types.
Temporal variation
Time affects a language, both in the long term and short term, giving rise to several highly distinctive processes and varieties. Long term: English has changed throughout the centuries, as can be seen from such clearly distinguishable linguistic periods as Old English, Middle English, and Elizabethan English. Language change is an inevitable and continuing process, whose study is chiefly carried on by philologists and historical linguists. Short term: English changes within the history of a single person. This is most noticeable while children are acquiring their mother tongue, but it is also seen when people learn a foreign language, develop their style as adult speakers or writers. and, sometimes, find that their linguistic abilities are lost or seriously impaired through injury or disease. Psycholinguists study language learning and loss, as do several other professionals, notably speech therapists and language teachers.
