In this paper, we offer an extension of an earlier proposal for treating wh-questions within a compositional, neurally–implemented semantic framework that interfaces with memory to the other main class of questions, namely polar questions. Our proposal yields improved empirical coverage for polar questions as compared with previous formal semantic accounts. It also offers the basis for an account of the finding that understanding for wh-questions emerges in language development before that of polar questions–a finding that goes against all previous formal semantics accounts of questions where polar questions are simplest in terms of their semantic complexity.