In forming questions, the child's first stage has two procedures. Simply add a Wh-form (Where, Who) to the beginning of the expression or utter the expression with a rise in intonation towards the end, as in these examples:
Where kitty? Doggie?
Where horse go? sir chair?
In the second stage, more complex expressions can be formed, but the rising intonation strategy continues to be used. It is noticeable that more Wh-forms come into use, as in these examples:
What book name? You want eat?
Why you smiling? See my doggie?
In the third stage, the required movement of the auxiliary in English questions (I can
have... = Can I have ...?) becomes evident in the child's speech, but doesn't automatically spread to all We~question types. In fact, some children beginning school in their fifth or sixth year may still prefer to form Who-questions (especially with negatives) without the type of inversion found in adult speech (e.g. Why kitty can't ...? instead of Why can't kitty ...?). Apart from these problems with We-questions and continuing trouble with the morphology of verbs (e.g. Did I caught ...? instead of Did I catch?) , Stage 3 questions are generally quite close to the adult model, as in these examples:
Can I have a piece? Did I caught Ir?
Will you help me? How that opened ?
What did you do? Why kitty can't stand up?