When you enter in room, usually first they ask you to introduce yourself. It would be awkward if you introduce in Urdu because they asked you in English. After Intro is done, they will ask questions related to your subject, then you can reply in Urdu. Don't seek for permission, just discuss in language you are comfortable. They are more concerned about your command on subject. The main thing is to convey your point clearly.

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There are certain questions that must never be asked. Of anyone. Even oneself.