第三条件句：后悔的时光机
后悔的时光机：如果我当时学习了，我就通过了。非真实过去——本可能发生的、本该发生的、从未发生的事。
第三条件句
后悔的时光机
第三条件句穿越到过去并改写它：如果条件当时不同，结果就会不同。过去已关闭——这就是本可能发生的事。
非真实过去
被重写的过去If I had studied, I would have passed
后悔
来得太晚的愿望If I had known, I would have called
批评
温和的责备If you had checked the map, we would not have got lost
关闭的门
过去无法改变If they had left earlier, they would have caught the train
⚠️ If + had + 动词过去分词，would have + 动词过去分词。被重写的过去。
公式
if + had + 动词过去分词 → would have + 动词过去分词
两部分都穿越到过去：条件部分携带 had + 动词过去分词，结果部分携带 would have + 动词过去分词。这台机器只能单向运行——过去无法改变。
⚠️ if 从句中使用 had + 动词过去分词，result 部分使用 would have + 动词过去分词。
常见错误
四种时光机失误
当 would 爬进 if 从句、when have 在结果部分消失，或两部分处于不同时态时，机器就会卡住。
If I would have studied, I would have passed.
If I had studied, I would have passed.
💡 if 从句中使用 had + 动词过去分词——不使用 would。
If I had studied, I would passed.
If I had studied, I would have passed.
💡 结果部分在 would 之后需要 have + 动词过去分词。
If I had studied, I will have passed.
If I had studied, I would have passed.
💡 非真实过去与 would have 搭配，不与 will 搭配。
If she had called me, I could helped her.
If she had called me, I could have helped her.
💡 could have + 动词过去分词——错过的机会。
快速测验
测试你刚刚学到的内容
三分钟，五道题——检查哪些记住了。没有作文题，我们保证。
If I had studied, I ___ have passed.
💡 附加信息2 个部分
虚拟语气阶梯
四个台阶，从总是到从不
四种虚拟语气构成一个阶梯：每个台阶让情况离现实更近一步。
If you heat ice, it melts
If it rains, I will stay home
If I had money, I would travel
If I had known, I would have called
⚠️ 一个阶梯，四个台阶：从始终为真到从未发生。
使用 Had + 动词过去分词还是 Would Have + 动词过去分词？
将一半与任务匹配
一个句子中有两个部分：条件部分和结果部分。每个部分都有自己的引擎。
⚠️ if 从句包含 had + 动词过去分词；结果部分包含 would have + 动词过去分词。