Grammar is the system of rules and principles for speaking and writing a language. It can be subdivided into the study of the internal structure of words (morphology) and the use of words in the construction of phrases and sentences (syntax); hence why grammar is also known as ‘morpho-syntax’.
However, grammar isn't just limited to these two fields. Since it governs structure, virtually all other fields of linguistics depend upon it. Phonology is closely linked with grammar because the sounds of morphemes, words and phrases are influenced by how the structures are organised – some of the most transparent examples of this include: Indo-European consonant & vowel mutations;
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