1．非真实条件句中虚拟语气的基本形式
(1)与现在事实相反
条件从句用过去时(be动词的过去式一律用were)，主句用“would (should/might/could)＋动词原形”。如：
If I were you, I would accept the invitation to the party.
如果我是你的话，我将接受去聚会的邀请。
(2)与将来事实相反
条件从句用过去时或者“were to＋动词原形”或者“should＋动词原形”，主句用“would (should/might/could)＋动词原形”。如：
If it were Saturday tomorrow, we wouldn't have an exam.
如果明天是周六的话，我们就不考试了。
