Expression de l’obligation et énonciation en russe contemporain : analyse de deux prédicats régissant un datif

In Russian there are two structures expressing obligation: a personal one (dolžen), with a nominative subject, in which the predicate agrees with it, and an impersonal one (nado and nužno), with a dative subject and an impersonal predicate. In both of these structures, the predicate can be verbal or nominal but it can be absent from the sentence (zero predicate) only in the impersonal structure. This paper focuses on the two impersonal predicates nado and nužno, which are usually given as synonyms in dictionaries as well as in linguistic papers. They are both used with a dative subject, indicating that the subject – not always present in the clause – doesn't control the process, and are followed by an infinitive (perfective or imperfective). However, there is a well-known difference between them in negative sentences: neg + nado + imperfective infinitive can express, depending on the context, interdiction or non-necessity, and neg + nužno + imperfective infinitive can only express non-necessity. Besides, Laufer (2007) has shown that the frequency of use of these two predicates varies a lot depending on the presence or absence of a dative subject in the sentence. This hints that they do not work the same way. The pragmatic terms of “necessity” or “need” do not allow us to understand these differences. As a result, we must take into account not only the type of expressed modality, but also the way it is constructed and uttered by the speaker