The aim of the paper is to address a case of a syntactic pattern involving context, which can be summed up by this assumption : a construction provides pieces of context that the speaker considers to be necessary for the addressee to get a relevant interpretation of the current utterance. There exist constructions which bring in background contextual information to maximize the "relevance" of the utterance they are added to. This piece of an utterance are not in fact part of the ongoing text, but have some kind of background status which makes them part of the context. At first glance, these pieces of utterances have, in the domain of speech, the same status as footnotes have in written uses of language. They are, strictly speaking, marginal to the text and nearer to context status than to plain text status. We will focus on a subgroup of these constructions, namely those which are introduced by grammatical devices (so called subordinators) and which appear as superficially synonymous with prototypical subordinate clauses