Semantic subordination despite syntactic coordination

In several respects, including binding and quantification, the left-hand conjunct in ''left-subordinating'' and-constructions (e.g., you drink one more can of beer and I'm leaving) behaves like a subordinate clause. However, treating it as syntactically subordinate results in an unnatural account of its superficially coordinate structure. Thus, the binding and quantification effects must be due to subordination at the level of conceptual structure, not syntactic structure. In addition, certain extraction and inversion phenomena in the left-hand clause are consistent only with its being coordinated in syntactic structure. A striking consequence is that the Coordinate Structure Constraint holds at conceptual structure, whereas Condition on Extraction Domain effects are strictly syntactic. The left-subordinating and-construction is thus another example of a significant mismatch between syntactic structure and semantic representation.