Complex syntax input: A single case investigation of increasing preschool teachers’ complement clauses in play interactions

This study investigated the feasibility of a vocabulary-based teacher intervention to increase preschool teachers’ production of complement clauses (e.g. I wonder if we can put the monkey in the tree) in teacher–children play interactions. Using a multiple baseline across participants design we measured the impact of an intervention that promoted preschool teachers’ production of four complement clause verbs (CCVs)—figure out, notice, remember, wonder. Based on visual analysis we established a functional relation between the teacher intervention and the teachers’ production of the target CCVs produced with a complement clause. Asking teachers to increase their use of CCVs in verbal interactions with children is a promising approach to increase teacher complex syntax input in the preschool classroom.