This title addresses the question of what types of elements are frequently used in discourse, and how frequency of use affects cognitive representations. It reports on evidence from natural conversation, diachronic change, variability, child language acquisition and psycholinguistic experimentation. The title also supports two major principles - firstly, the content of people's interactions consists of a preponderance of subjective, evaluative statements, dominated by the use of pronouns, copulas and intransitive clauses. Secondly, the frequency with which certain items and strings of items are used has a profound influence on the way language is broken up into chunks in memory storage, the way such chunks are related to other stored material and the ease with which they are accessed to produce new statements.