Sentence:  Causality in the <WSD>Intentionality</WSD> Model is in the agency of the child. It is the child who perceives, who apprehends, who constructs the intentional state, who acts to express it, and who interprets what others do (including what they say) to construct a new intentional state. 
Meaning of the word marked with <WSD> tags:  the characteristic of a mental state whereby it is "about" something, which relates to mental states in an analogous way as meaning relates to a word