because 习惯上不与 so 连用.汉语习惯上说“因为…所以…”,但英语习惯上却不能将 so与because 连用：
因为下雨,所以我们呆在家里.
误：Because it was raining,so we stayed at home.
正：Because it was raining,we stayed at home.
正：It was raining,so we stayed at home.