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The Langfocus youtube channel came out with a new video on Japanese. In it he explains that the が can be used to express focus. I have never heard (probably not paid attention) or learnt this. So, my question is: is this standard Japanese, or rather colloquial use?

ドーナッツが食べたい instead of ドーナッツを食べたい to express focus on "donut"

marked as duplicate by Chocolate, l'électeur, virmaior, naruto, macraf Jul 2 '17 at 3:49

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