In formal semantics and pragmatics, modal subordination is the phenomenon whereby a modal expression is interpreted relative to another modal expression to which it is not syntactically subordinate. For instance, the following example does not assert that the birds will in fact be hungry, but rather that hungry birds would be a consequence of Joan forgetting to fill the birdfeeder. This interpretation was unexpected in early theories of the syntax-semantics interface since the content concerning the birds' hunger occurs in a separate sentence from the if-clause.