The Notion of Correctness

Whether a piece of language is "right" or "wrong" is frequently a misleading idea. In practice, language may better be described as "appropriate" or "acceptable" to a given register or context.

What is acceptable when spoken by a teenager may not be acceptable when written in a report by an adult. Context is all.

The so-called "rules" of English are usually in fact pieces of advice laid down by grammarians who refer back to classical models, even though the structure of Latin and Greek are very different from English. They are sometimes referred to as "nineteenth century neo-classical grammarians."

Some of these "rules" may be good advice for a speaker looking for a model of clarity, but others are now widely seen as artificial constraints on a living language.

Rules such as "don't finish a sentence with a preposition", "don't start a sentence with 'and'" and "don't split an infinitive" are examples of rules which are held to by some language users but deliberately flouted by others.

Note that grammatical rules are generally more advisory than the rules governing the meaning of words. Although words do change their meaning, have ambiguity and frequently have several meanings at once, a dictionary definition is, by and large, an agreed meaning of a word. Lists of commonly confused words can be helpful in distinguishing between "whet" and "wet" or "complement" and "compliment" for example. Visit one such list here at Awesome Grammar.

There are two main principles at work creaeting grammatical rules:
Prescriptive describes the attitude that there are rules and you should obey them.
Descriptive describes the attitude of many modern linguists which is that what is said by natural speakers of the language is normal and that this "real" language should be described by students of linguistics to create a model of language.
In other words prescriptive grammarians impose their views based on prescribed or laid down rules while descriptive grammarians describe the language first then offer this as a framework within which users can work.

Underpinning all this are basic rules which are generally agreed, fundamental rules which make a language unique.

Does Your English Let You Down?