Around the age of four or five the child lemmas have a wide range of diversity, this helps them select the right lemma needed to produce correct speech. Reading to infants enhances their lexicon. At this age, children who have been read to and are exposed to more uncommon and complex words have 32 million more words than a child who is linguistically impoverished. At this age the child should be able to speak in full complete sentences, similar to an adult.