The capacity to successfully use language requires one to acquire a range of tools including phonology, morphology,syntax, semantics, and an extensive vocabulary. Language can be vocalized as in speech or manual as in sign. The human language capacity is represented in the brain. Even though the human language capacity is finite, one can say and understand an infinite number of sentences, which is based on a syntactic principle called recursion. Evidence suggests that every individual has three recursive mechanisms that allow sentences to go indeterminately. These three mechanisms are:relativization, complementation and coordination.[3] Furthermore, there are actually two main guiding principles in first-language acquisition, that is, speech perception always precedes speech production and the gradually evolving system by which a child learns a language is built up one step at a time, beginning with the distinction between individual