释义
conj. 除非 prep. 除...外
例句
1. I won't go to the party unless I'm invited. 除非我被邀请，否则我不会去参加晚会的。 2. I sleep with the window open unless its really cold. 我总是开著窗户睡觉, 除非天气非常冷才关上窗户.
