Although the majority of language development occurs in infancy and pre-school years, development continues through adolescent years. Linguistics development during this time is subtle but important. This development includes learning to use more complex language and to communicate differently depending on the situation. At this time, children grow their vocabulary and learn the proper and underlying use of each word. They also develop syntactic sentence formation. Adolescents use of language also reflects their sensitivity to how their peers perceive them. For example, to use foul language in an attempt to fit into peer group or to prove he is tough enough.