Every sentence is a certain syntactic construction. One can specify that, like any other structure, the sentence is bearing main frame and part which can be eliminated without damaging the structure, in other words a kind of 'architectural redundancy’. In possibility / impossibility of omission, manifest itself the importance of syntactic element for the structure, of which it is a part. Thus, one can talk about constructive significance of the sentence parts.
29–30 November, 2014