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Do you know what his name is?

Do you know what is his name?

I saw this in grammar text book. The first is the correct one because "Subject + Verb". The second is wrong.

We do usually say "What is your name?", "What is his name?", why the sentence is wrong when the front of the question is "Do you know..."

marked as duplicate by J.R. Oct 27 '14 at 8:55

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