This isn’t a breakthrough or anything, but I’m impressed that two-year-olds know how to conjugate verbs.
That is, my daughter doesn’t just use words she hears. She actually changes those words in order to use them in ways that she hasn’t heard. And I know she does this because she makes mistakes on the irregular verbs.
For example:
I live. He lives.
I go. He goes.
You add a Z sound to end of those verbs when saying “he” or “she.”
And my daughter said:
He dooz.
In other words, “I do. He dooz.”
She had never heard anyone say that before, but she knew without thinking about it how to conjugate a verb. In this case, the verb is wacky, so she got it wrong, but most of the time she’d be right.
She also said that she wanted to listen again to the song “we just heared.”
Again, she knows that past-tense verbs take a D sound. No one around her had ever said “heared,” but she constructed it herself, on the fly.
I don’t look at these things as cute mistakes, but as amazing powers of learning.
I want to say “she’s right; the language is wrong.” She is quite bright, and it doesn’t hurt that you talk to her like a real person. We did the same, and people were surprised at how well our daughter spoke as a young child. The only person who used “baby talk” or similar was my mother-in-law, who probably did it primarily to upset us. Children really do learn by example, and can understand rules and form generalizations better than some adults expect. That, and some just have good genes to start with.
The crazy thing is that all normally developing kids figure it out no matter how their parents talk to them.
They could take a gibberish word:
speckwist
And conjugate it:
I speckwist
He speckwists
Yesterday I speckwisted.
I think it slows kids’ development a lot to have people say things like “does we wants a lollipop?” and similar. If it’s just nonsense words, then no problem, but typical baby-talk involves messing up tense, etc. as well. Eventually, the child gets old enough to escape this confusing environment (who baby-talks to a six-year-old?), but it’s bound to retard their development until then.