In this preschool study, the use of complex sentences (sentences with clauses - like "The boy likes the dog in the window, but it is not for sale) improved children's language development. The caveat for this, though, is in the presence of auditory processing disorders or specific language impairment. Always look to see if children are able to keep up with challenging ways of speech. If they can follow you,
you're building brain connections!
Research shows teacher and parent conversation important in child language development