Abstract: The domain of space presents some interesting properties.On the one hand, spatial understanding by human beings is said to be universal and to share the same biological heritage; on the other, the linguistic systems encoding spatial knowledge vary strikingly.This paradox raises fundamental questions, among other things, for the study of first language acquisition: when children acquire spatial expressions in their own language, are they constrained by a universal set of cognitive determinants or rather by the specific linguistic means available in their language from early on? Or do both cognitive and linguistic determinants influence the developmental path of these child L1 learners? The present study investigates the expression of voluntary motion events by Chinese and English children across ages in cartoonbased production tasks.Our results show first of all that typological properties influence the semantic density of children’s utterances.Regardless of age, children express denser semantic information in Chinese than in English because of the availability in Chinese of easily accessible resultative verb compounds which facilitate the simultaneous encoding of varied semantic components for motion.Second, a striking developmental progression occurs in English between the ages of three and five and adulthood, whereas in Chinese no such developmental progression can be observed.Generally, the present study highlights the implications of typological constraints for the debate concerning universal versus language-specific determinants in language acquisition.