  H1 generates the ungrammatical question (3b), whereas H2 generates  the correct version,   (3c).[6]  Now, you and I and every other English speaker know (in some sense  — see §3.2.1a) that H1 is false and H2 is correct.  That we know this is evident, Chomsky argues, from the fact  that we all know that (3b) is not the right way to say (3c). The  question is how we could have learnt this.