A growing body of research suggests that language users integrate diverse sources of information in processing and adapt to the variability of language at multiple levels. In two visual-world paradigm studies, we explored whether listeners use prosody to predict a resolution to structures with a PP that is structurally ambiguous between a modifier and an instrument interpretation. The first study revealed that listeners predict a referent that is most compatible with the location of a prosodic boundary, casting anticipatory looks to the appropriate object even before the onset of a disambiguating word. The second study indicated that listeners failed to anticipate instrument resolutions when the prosody of non-experimental filler items was unconventional, even though experimental items remained identical to the first study. The results suggest that listeners adjust their predictive processing to the utility of prosodic information according to whether a speaker reliably conforms to the conventional use of prosody.