The document discusses several linguistic concepts including phonology, phonemes, morphemes, morphology, syntax, and grammaticality. It provides examples and definitions of: - Phonemes as the smallest units of sound that convey meaning. There are vowel, consonant, and diphthong phonemes. - Morphemes as meaningful units of a word, including inflectional morphemes that indicate grammatical function and derivational morphemes that create new words. - Syntax as the rules that determine how words combine into phrases and sentences, including parts of speech and phrase structure. - Grammatical versus ungrammatical sentences based on conforming to or violating syntactic rules.