How to beat fear?

By the sense of responsibility. In a dangerous situation you should think you're not alone. You have your family, friends and colleagues behind you. You've been selected by them to fight in the battle.

I don't know, but ...

A good friend advised me to say "I don't know" to the questions that I don't have a clear answer for. And more importantly I should immediately connect the question to my current knowledge and shoot a new question back to my partner in the conversation. Making no question may indicate my lack of interest to the partner's topic.

Example
Question: Do you know anything about vegetable X?
Bad answer: No, I don't know.
Good answer: No, I don't know. Isn't it green like vegetable Y?
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