Young children learn about causal structure not only from observation, but also from the language they hear. Two novel-verb studies show that preschoolers expect transitive sentences like "Sarah broke the lamp" to express relationships between cause and effect. Previous work has conflated causation with other semantic features, presenting children with coarse contrasts between scenes varying on multiple dimensions. The current studies used minimal-pair scenes that varied on a single causally-relevant feature, the spatiotemporal contiguity between action and outcome. Preschoolers were more likely to produce transitive descriptions ("She wugged it") to describe causal versions of events. They also reliably selected causal versions when asked to "find where she wugged [it]". Transitive syntax thus provides children with a rich source of evidence about the verbs they learn and the events they encounter in the world.