Ming from Agents of Speech explains why speech-delayed children repeat whole phrases they've heard, like "Are you okay?" without understanding them. They lack the vocabulary to build their own sentences, so the fix is giving them more words to work with.
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A lot of my students, they fall down and say are you okay? As a chunk that they learned from their mom because their mom would say are you okay the first thing or are you hurt? Right? And then the kid would be like, are you okay? Are you okay? And holding on to their knee like this, right? Are you okay? So that's the gestalt part that they got from the mom through many repetitions and they found it off. That's amusing. Let me use it. But they use it in the wrong way, meaning they don't understand that it was a question answering. You know, they didn't say I'm in pain or I hurt myself or ouchie. Right. So it's the wrong use of language that's the problem. How do you deal with this? You have to make sure that your child has enough words to combine words into sentences and phrases.