Originaltext - Englisch - The functions of language

The analysis of discourse is, necessarily, the analysis of language in use. As such, it cannot be restricted to the description of linguistic forms independent of the purposes or functions which those forms are designed to serve in human affairs.
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That function which language serves in the expression of “content” we will describe as transactional, and that function involved in expressing social relations and personal attitudes we will describe as interactional.