I did not tell my daughters to 'play games (such as on their phones)' or 'don't play games.
However, I have never encountered the phenomenon many parents are annoyed with: 'My child won't leave the game.
I did not tell my daughters to 'read books' or 'don't read books.
But they seem to be reading books just fine.
I didn't even tell my daughters to 'study.
I don't know if they excelled, but they seem to have graduated, so I think they did reasonably well.
I had told my daughters, 'You might do English.
However, my two daughters have summed it up by saying, "At least we didn't need English at all for 'job hunting.
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It wasn't until I was over 30 that I started studying English "with my life on the line." My life was on the line.
I managed to work abroad. I am still managing to do so.
Incidentally, as far as I know, there is no data to support the claim that 'if you don't start at an early age, you can't use English' (the only company that claims so, without evidence, is the company that produces English materials for young children).
Please let me know if you have any data or papers to back this up. I will use an engineering approach to validate it properly.
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Anyway, I have no "educational theory" to speak of.
The only exception is my memory of doing this.