The imitation theory focuses on the habit children have of repeating what their parents say. This is a widely recognized trait of young children. The theory suggests that imitation is the basic by which children learn a language. Parents play an important role in speech development for this particular hypothesis. There are two interesting habits of most parents that directly relate to this theory of language learning. First, parents seem to naturally adapt their normal manner of speaking to suit infants and very young children. They change their voice and speak in much simpler sentences. This kind of language is know as child-directed speech, or more informally motherese.