First dates are little awkward so it is inappropriate to ask the personal question during your meeting. In order to avoid the uncomfortable silence, you could talk about the casual things. Here are the some questions you should never ask.
1) Why were you single up to this time?
2) What went wrong with you and your ex?
3) How much money do you make in a month?
4) Why haven’t you send me a friend request on Facebook yet?
5) When did you lose your virginity?
6) So, when are you planning to get married and have kids?
7) Are you attracted towards me?
8) Do you think that girl is pretty than me?
9) Do you mind if I order another dessert for me?
10) Where do you see this relationship is going?
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So, these are the list of the questions you should never to try to ask. Stay calm and play it cool.