2016高考英语必考范围大揭秘：unless…除非，如果不……
unless…"除非，如果不……"(=if…not) [例句] I shall go tomorrow unless it rains. 如果不下雨，我明天去。 -Shall Tom go and play football? -Not unless he has finished his homework. 除非他完成作业，否则不能出去。 I won't go unless he comes to invite me himself. 除非他本人来邀请我，不然我是不会去的。 I won't attend his birthday party unless invited (=unless I am invited). 除非被邀请，否则我不去参加的生日晚会。