for 有介词和连词两种用法 介词如：what can I do for you. I'm waiting for you. I have stay here for years. 做连词时,其用法和because基本等同 如I beat him,for he made me irate. 但通常情况下,because作为连词意味因为比较普遍. so作为连词时意思为“那么,因此,所以”,后面强调的是结果 It's raining hard,so I won't get to school on time. 也可以做副词,表示,“如此,如是” 如Time goes so quick. I like to do so.
