本期内容：
All things in their being are good for something
天生我才必有用
all things in their being 可以理解为所有存在的事物这里我们可以学习一个短语 be good for sth 对什么有益be good for health 对健康有益be good for the environment 对环境有益它的反义词是be bad for something 对什么有害一切存在的事物都有他存在的理由
