In the case of negatives, Stage l seems to involve a simple strategy of putting No or Not at the beginning, as in these examples:
no mitten not a teddy bear no fall no sit there
In the second stage, the additional negative forms don't and can't appear, and with no and not, are increasingly used in front of the verb rather than at the beginning of the sentence, as in these examples:
He no bite you I don't want it
That nor touch You can't dance
The third stage sees the incorporation of other auxiliary forms such as didn't and won't while the typical Stage 1 forms disappear. A very late acquisition is the negative form isn't, with the result that some Stage 2 forms (with not instead of is't) continue to be used for quite a long time, as in the examples:
I didn't caught it He not taking it
She won't let go This not ice cream
The study of the developing use of negative forms has produced some delightful examples of children operating their own rule for negative sentences. One famous example (from McNeill, 1966) also shows the futility of overt adult "correction" of
children's speech.