Child Language Acquisition - data set

And just to be on the safe side, here's a quick 1a style question on CLA. All you have to do is identify and label 3 "interesting" features from the data set below:

Data set:

1. I readed that book yesterday.
2. What that man doing?
3. Dat's gusting. I not like that dinner.
4. My tooth is hurty.

If you give your points as comments, I'll try to give you some feedback (my own child language data providers permitting).