Tomasello - Chapter 5

This chapter was very interesting with Tomasello describing the Verb Island Constructions, and of course, again makes me excited to go home this weekend and verb test my 22-month-old niece. Though she is on the younger end of verb testing, I'm still gonna do it.
The amazing thing about this study is the fact that the children can differentiate between the word usage in the examples. Although Tomasello suggests it is not the same process as learning a different language, it does bring me back to Spanish class and having to use context clues to figure out what the new word presented means, however when I was doing this in class, I knew exactly what I was attempting to do:

*Question: Do children know they're using context clues to determine new words/concepts?

*Question: I'm wondering if making up fake words to test this is fair for children? I figure it isn't that big of a deal because after the experiement they don't hear that word again, but doesn't it seem unnatural to use words that mean nothing for these tests? Is the goal to use a word that the child has never encounterred so that we see what reaction he/she has? But isn't that unnatural too since it is highly unlikely that the first time a child understands "put" or "ball" is the first time the child has actually heard the word?
I'm curious to anyone's thoughts about this.

Also, I agree with the chapter's conclusion that children mostly learn via imitative learning.