how does a person master his fate?does是起什么作用的?

how does a person master his fate?does是起什么作用的? He does not know how to dispose of his spare time中of起什么作用去掉o Does he have a stomach ache 请问里面的这个a是起什么作用?怎么翻译? How much water does a person need for a day? How does the law define a reasonable person? How a person masters his fate is more important than what hi fate 里的MASTER How does he like his how does Peter like his How does A like his job?如何回答? For man is man and master of his fate 这么翻译对吗 .（人就是人 是自己命运的主人 How much does it cost? 中的"does"中这句中是起到什么作用?表示什么意思