"Learning a language is child's play"
The ANU College of Medicine, Biology and the Environment:
Very young children usually cannot remember a few words that you tell them, but they can somehow master complex grammar. ANU researchers have been investigating this peculiar riddle, which indicates that learning a language is child’s play.
Some people think that because very young children are good at learning languages, they have an innate knowledge of language—like a programmed robot. One theory, for example, is that children are born with an expectation that languages have verbs and nouns.