A、External. B、Subjective. C、Interpersonal. D、Imperative. BWhat is the essential characteristic of the psychological functions?

In order to have a more satisfactory understanding of what is involved in interlingual communication, it is essential to view first the major functions and theories about language. By considering many of the diverse functions of language it is possible to understand better the amazing complexity of verbal communication, and a brief look at the more important major theories about language can provide a much more satisfactory means of understanding how people communicate.
    The functions of language are of two basic types: psychological and sociological. The psychological functions may be described as the means by which people negotiate with reality. The psychological necessity to give names to experience is so obvious that people sometimes fail to realize its significance until they have read the stirring story of Helen Keller and the power insights gained by her discovery of a symbol for water. The sociological functions can be said to be those ways by which people negotiate with other persons. They are of the following types: interpersonal, informative, imperative, performative, and emotive. The psychological functions may be regarded as essentially internal or subjective, and the sociological functions as external and interpersonal.