why 和 because 都可以引导表语从句,它们有何区别?
前因后果用why; 前果后因用because:
He was ill. That's why he was sent to the hospital. 他病了(原因),所以被送到医院来(结果)。
He was sent to the hospital. That's because he was ill. 他被送到医院(结果),是因为他生病了(原因)。
[例句引自英语语法网]