The aim of this paper is to focus on the so-called no man's land where sociolinguistics and grammatical theory interact. It is argued that E-language as a social and I-language as a psychological construct do not exist independently, but influence each other. In other words, syntactic variation and change are driven by social factors but constrained by the nature of possible grammars. The interaction between the social meanings of linguistic forms on the one hand and grammar on the other brings about complex and multi-layered relationships between the individual and the group's or societal grammar. This paper emphasizes how individuals are restricted by grammar but, at the same time, able to overcome these restrictions in specific situated contexts through interactions. This combined approach enables us to predict why some structures are more resistant or vulnerable to syntactic variation and change than others and the route(s) individuals may take to overcome syntactic "restrictions". In this process of interdependent relations between the I-and E-languages, the interpretation and evaluation of linguistic forms through interaction is of crucial importance in the realization of so-called "impossible" or "unrealized" constructions.