What is grammar? Rules, varieties, and grammaticality

In linguistics, grammar is not just a list of school rules about “correct” language. According to 1-What-is-language-24, all languages have grammar, meaning a system of phonological, morphological, syntactic, and semantic rules. These rule systems are part of speakers’ unconscious knowledge of language and help them produce and understand sentences.

Grammar as a system of rules

1-What-is-language-24 explains that grammar includes several connected components:

• Phonological rules: rules about the sound system of a language and how smaller units of sound pattern together.
• Morphological rules: rules about word structure, such as how roots and affixes combine.
• Syntactic rules: rules about how words combine into phrases and sentences.
• Semantic rules: rules related to meaning.

Together, these components make language systematic. The source also notes that language messages are made from smaller repeatable parts and can be recombined in many ways. This helps explain how speakers can create and understand new utterances.

What counts as grammatical?

In linguistics, grammaticality usually refers to whether an expression follows the rule system of a language variety, not whether it matches a social standard of “good” usage. This is why linguists distinguish between the grammar speakers actually use and the rules some authorities say they should use.

Descriptive grammar vs. prescriptive grammar

1-What-is-language-24 makes an important distinction between descriptive and prescriptive grammar.

• Descriptive grammar describes the rule system speakers actually use to produce sentences, regardless of the social value attached to those sentences.
• Prescriptive grammar gives rules for how people are supposed to speak or write, usually according to an authority such as a teacher, parent, or handbook.

The source illustrates this with the contrast:

• I don’t know who to see.
• I don’t know whom to see.

Under prescriptive grammar, the second sentence may be labeled the “correct” one. But descriptively, many speakers are more likely to use the first sentence in everyday speech. This shows that a sentence can be natural and rule-governed in actual usage even if it does not match a formal prescriptive rule.

Grammar across varieties and dialects

1-What-is-language-24 states that a language is really a continuum of language varieties. This means that what we call a single language often includes multiple dialects or varieties, each with its own systematic grammar.

Linguists generally consider two varieties to be dialects of the same language if their speakers are mutually intelligible, meaning they can understand each other. Mutual intelligibility is therefore a useful guideline for distinguishing a language from a dialect.

However, the source also emphasizes that this distinction can be fuzzy:

• Sometimes two varieties are considered part of the same language even though speakers do not understand each other very well.
• Sometimes two varieties are labeled separate languages even though speakers can understand each other, often for political, social, or geographic reasons.

So, mutual intelligibility is important, but naming something a “language” or a “dialect” is not always based on linguistic structure alone.

Key idea to remember

Based on 1-What-is-language-24, grammar is best understood as the internal rule system that organizes language at the levels of sound, word formation, sentence structure, and meaning. Linguists describe these systems as they are actually used, while prescriptive traditions judge forms according to social standards. Language varieties and dialects are also systematic, and their relationship is often discussed in terms of mutual intelligibility.