1) The document proposes adding two new constructs, rdf:context and rdf:imports, to make contexts explicit in RDF graphs. 2) rdf:context would associate a context definition with an RDF graph, and rdf:imports would represent how knowledge is transferred between contexts during import operations between graphs. 3) Making contexts explicit would allow for reasoning about compatibility between contexts and partial reuse of knowledge between contexts through relations like compatible and incompatible.