In his book, Steven Pinker relates two main issues: the way children learn their mother tongue, and how their mind represents fundamental categories of meaning such as space, time, causality, agency, and goals. Therefore, the same concept expressed in diverse ways may result more or less complicated for children to understand and express. Pinker presents a theory of how children acquire the meaning and usages of verbs, and investigates this theory’s implications for language, thought, and the relationship between them.