This document discusses various grammatical features of language. It defines grammatical features as the elements that words can be broken down into, such as number, person, and tense. It then provides examples of special grammatical features like register, which determines what is appropriate in certain contexts. Collocations are discussed as words that commonly go together, like "stiff wind." Learning collocations is important for natural speech. Word class or parts of speech are also covered, with examples like nouns and verbs.