earn是赚的意思，而obtain则是获得的意思，区别可以从以下例子看出：
After work, boss paid me, that is the first money I earn by myself, also I have obtained working experience, it is very good. 下班后老板给我发工资，那是我自己挣的第一笔钱，也获得了工作经验，很好。
水利万物而不争,
而万物莫能与之争。
