EN
The problem area of the history of parts of speech is rather complex. The range of topics belonging here does not only include changes of part-of-speech affiliation (conversion, zero derivation, transmutation) but also a number of other issues like various ways of word formation by which certain word classes become larger, their stock increases by lexicalisation or like the problem of what syntactic reasons or circumstances, formal or functional aspects of the system play a role in the creation of new lexical items. In addition to individual words (the issues of word formation and conversion), the changes of word classes as wholes (for instance, cases where a new part of speech emerges, becomes part of the system, like conjunctions or articles) have to be investigated, as well as the consequent modifications of the whole part-of-speech system.