Clause types and speech acts in speech to children

The question of how and when children learn to associate clause type with its canonical function, or speech act, is currently unknown. It is widely observed that declaratives tend to result in assertions, interrogatives in questions, and imperatives in requests. Although such canonical links between clause type and speech acts are principled, they are known to be defeasible. In this corpus study, we investigate how parents talk to their children in the first years of life, and ask how their input might support this mapping, and to what extent it might pose difficulties. We find that the expected link between clause type and speech act is robust in the input, particularly between declaratives and assertions, both of which also occur most frequently. In addition, the non-canonical mappings that do occur are characterized formally, e.g., non-interrogative questions nearly always exhibit rising prosody, and non-imperative requests often contain a modal.