5. The method as claimed in claim 3 , wherein the expression is classified as learning when the expression is a Subject Verb Predicate (SVP) expression, and wherein the classification of the expression as learning comprises: retrieving at least one fact from the SVP expression, comprising at least two nodes and a relationship between these nodes, wherein the fact is being taught by the user; storing the fact in the user graph, wherein the user graph comprises a user node, and the at least two retrieved nodes and the retrieved relationship between these nodes; computing a confidence score for the at least one fact, wherein the computation is based on a plurality of parameters, determining the context of learning and validity of the fact thereof; and storing the fact in a factstore when the confidence score of the at least one fact is above a pre-defined threshold value.
6. The method as claimed in claim 5 , wherein the plurality of parameters comprise a source of a fact, frequency of a fact, fact confidence, credibility of a user, and association with other entities previously discussed/taught by a user.