Despite their considerable communicative abilities, young children often have difficulty interpreting complex linguistic structures in context. Two examples of this phenomenon are negation and pragmatic implicature, both of which pose sometimes surprising difficulties for preschoolers. Both of these structures require children to resist a more salient alternative interpretation; since executive function abilities develop extensively during childhood, perhaps failures are due to problems in inhibition. To test this hypothesis, we designed speeded tasks to measure inhibitory control, negation, and implicature comprehension in children and adults. Using standard analyses as well as drift diffusion models, we found different patterns of processing on all three tasks, and no support for the hypothesis that inhibitory control per se is playing a role in either adults' or children's negation or implicature processing. Instead, our analyses reveal qualitatively different developmental trajectories for each task, suggesting task-specific factors driving these changes.