One language becomes several

A. We have seen some of the tendencies in how languages change: assimilation, consonant weakening, vowel weakening, and sound shift.

B. But all of these processes can happen in many different ways, and there is no way of predicting which will occur in a language. For example, the th sound in thing has changed to a t in dialects where the pronunciation is ting (dem tings), but to f in Cockney English (dem fings).

C. Often, many groups of people speaking the same language have migrated to several different locations. Chance has it that different changes occur in each new place, and the result over time is several new languages.