Structural economy in the processing and representation of gapping sentences

The processing of ellipsis sentences can provide clues to their structure, as their structure can influence their processing. We present two studies examining the processing of a previously unexplored subclass of ellipsis sentence, gapping sentences in which one of the remnants is a preposed PP (PPGs). Like some other gapping structures, PPGs are ambiguous between readings in which a DP remnant is interpreted as a subject or as an object. However, we find that PPGs exhibit a weaker and more flexible object bias than other ambiguous gapping sentences (Carlson 2001a, 2002), one comparable to clausal ellipsis constructions like comparatives and replacives. We argue that this result supports the syntactic assumption that gapping is a non-uniform phenomenon: PPGs involve clausal conjunction on either reading, much like comparative ellipsis, while regular gapping has a non-ellipsis alternative (Johnson 1996), which underlies the strong preference for an object reading.