Do you believe in luck

I don't believe luck. Because i think anything you have to try your best to  prove it. You could't  always successes  by luck. I don't think some people are lucky than others. Lucky people try harder than the unlucky people. Lucky: Success or failure apparently by chance rather than through one's own action. Or having, bring, or resulting from good luck.  I know a person who are really unlucky. There is a man byt the lottery and won a million dollar. Then he went to Las Vegas to the Casino, he won a lot of money too. There is a another person, who bought thousands dollars, never won any money back.