Language is not a static entity. It changes over time. The change may be semantical, phonetic, morphological or syntactic. It is the job of historical linguists and evolutionary linguists to study this language change. There are certain causes that lead to changes in a language, what are these?
• Economy – People tend to shorten words wherever possible to facilitate faster and easier communication. Phonetic reduction is also an example of economy practiced in language.
• Migration – When language speakers migrate from one area to another, the language they use becomes diluted and borrows from the local language of their current location.
• Flawed learning – An immigrant group can learn a language improperly and then use it in this manner. Their usage will gain popularity in their community and may even overwhelm majority usage, becoming a new standard in itself.
• Contact with other cultures – As already discussed above, coming into contact with other cultures and languages impacts a language. It borrows terms and expressions to supplement their own grammar.
• Reanalysis – Some new words and expressions may be better suited to convey certain events/situations than what was used formerly.
Language keeps changing to reflect societal advances and we shall try to keep up.