ABSTRACT
Words are usually subdivided into those which belong to closed sets and those which are found in open classes. By closed set we mean that there are a finite number of items in the set. Conjunctions, determiners, exclamations, prepositions and pronouns belong to closed sets. Adjectives, adverbs, nouns and verbs belong to open classes, which means there are many items in these classes and we can add more. If we invented a new soft drink called ‘shing’ for example, we would have a new noun, and if drinking shing became popular, we might have a ‘shing party’ at which we would all ‘shing’, thus adding a new adjective and verb to the language.
