What is beautiful ?

How will you describe beauty? For some a round face would look beautiful while for some an oval. I have often heard people judge girls on their beauty, but I never understand how they can do that. I can say what looks beautiful to me, but I can never tag a girl as beauty queen, for I know that others may not find that girl/ boy as beautiful as I.

For example, my mother in law believes that my kids are not beautiful, but for me they are the most beautiful kids existing on this planet, so who is right? Well, it is all about personal choices.

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I have often seen people marry for beauty, how safe is that? Beauty fades away with age, if beauty is the criteria for marriage, wouldn't it be at risk when you get old? I believe nature should be more important than beauty because a person's nature would remain same in whatever life conditions it be.