条 件 与 现 从句谓语用一般过去时(be多用were)
在 事 实 相 主句谓语用 would / should / could /
反
might+动词原形
【完成例句】 (3)如果你早点来,你就不会错过那辆公共汽车了。 If you had come earlier, you couldn't / wouldn't have missed the bus. (4)如果他昨天见到了你,他就会还你的书的。 If he had seen you yesterday, he would have returned your book.
【疑难剖析3】if假设条件从句谓语动词发生的时 间与主句所假设的谓语动词不一致,叫做错综条 件虚拟语气。主句和从句的谓语动词要依照假设 的时间而定。
(二)用虚拟语气,从句中谓语时态相应推后(即用 相应的过去时态)的五种句型 【完成例句】 (7)他多么希望自己是只鸟。
How he wishes that he were a bird. (8)我希望昨晚看了那部电影了。
【结论2】
条件与过去 从句谓语用had done 事实相反 主句谓语用would / should / could /
might+have done
【完成例句】 (5)万一明天下雨,运动会就推迟。(事实上明天下 雨的可能性不大。) If it should rain / were to rain / rained tomorrow, the sports meet would be put off. (6)万一杯子掉下来会打碎的。 If you dropped / should drop / were to drop the glass, it would break.