Child bilingualism
Children who are exposed to two or more languages from birth must not only master the art of speech and communication; they must also sort out which linguistic structures and forms are appropriate in which situation. Many researchers have observed that young bilingual children tend to mix their languages in ways that adult bilinguals do not; in other words, children seem to have difficulties keeping apart the elements of their linguistic repertoire and assigning them consistently to two or more different systems. Some researchers have suggested that the mental capacity to develop such separation only emerges in later childhood, though this conclusion is not accepted by all. Children are often creative, by-passing limitations on their vocabulary by 'inventing' new constructions and forms.