The document discusses morphemes, which are the smallest units of meaning in language. It provides criteria for identifying morphemes and examples of analyzing words into their constituent morphemes. Affixes are defined as bound morphemes that can only be used when added to other morphemes. The major types of affixes - prefixes, suffixes, infixes, and circumfixes - are identified. Examples are given of combining bases with affixes to form new words. The document also distinguishes between derivational and inflectional affixes and provides examples of identifying affixes as derivational or inflectional.