Theoretical linguistics

Theoretical linguistics is the branch of linguistics that is most concerned with developing models of linguistic knowledge. Part of this endeavor involves the search for and explanation of linguistic universals, that is, properties all languages have in common. The fields that are generally considered the core of theoretical linguistics are syntax, phonology, morphology, and semantics. Although phonetics often informs phonology, it is often excluded from the purview of theoretical linguistics, along with psycholinguistics and sociolinguistics.
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