bowwow theory comparative linguistics derivation descriptive grammar descriptive linguistics dialectology dingdong theory etymology generative grammar glossology glottochronology glottology grammar grammatical analysis grammatical theory grammaticality graphemics historical linguistics language study lexicology lexicostatistics linguistic geography linguistic science linguistics mathematical linguistics morphology morphophonemics paleography parsing philology phonetics phonology phrase-structure grammar psycholinguistics rules of language school grammar semantics sociolinguistics stratificational grammar structural grammar structuralism syntactics tagmemic analysis traditional grammar transformational grammar transformational linguistics