was/were+过去分词

现在进行时

am/is/are being+过去分词

过去进行时

was/were being+过去分词

一般将来时

will be+过去分词

过去将来时

would be+过去分词

现在完成时

have/has been+过去分词

过去完成时

had been+过去分词

情态动词

情态动词be+过去分词

考点名称：虚拟语气句

• 虚拟语气:
  用来表示说话人的主观愿望或假想，而不表示客观存在的事实，所说的是一个条件，不一定是事实，或与事实相反。
  虚拟语气通过谓语动词的特殊形式来表示。

• 初中阶段主要学习在条件句中的虚拟语气。
  条件句中的虚拟语气根据不同的时间有三种不同的形式。
  

  时间	条件从句	主句	例句
  与现在事实相反	If+主语+过去式（系 动词be多用were）	would 主语+should+V原  could	见①②句
  与过去事实相反	If+主语+had+过去分词	Would 主语+should+have+过     去分词  could	见③④句
  与将来事实相反	过去式     If+主语+ should+V原  were to+V原	would 主语+should+V原   could	见⑤⑥句

  例句：
  ① If I were rich, I would travel around the world.
  ② If I won a million dollars, I would give it to charities.
  ③ If you had taken my advice, you wouldn’t have failed.
  ④ If I had known that earlier, I wouldn’t have done it. 
  ⑤ If he should go to Tsinghua University, he would make full use of his time.
  ⑥ If he were to come here, he would tell us about it.

• 虚拟语气误区:
  1.混合条件句的主从句时态不会灵活变化；
  2.省略if时，句子调整不正确；
  3.不会去找意思中的“应该”含义；
  4.陷在虚拟中出不来，把真实条件句当成虚拟条件句。
  
  省略虚拟条件:
  1.省略连词if
  有时可将条件从句的连词if省略，但此时应用倒装句型，即把从句中的were,should,had 等提到句首：
  Were I Tom,I would refuse. 如果我是汤姆，我会拒绝。
  Should it be necessary,I would go. 假若有必要，我会去的。
  Had it not been for the bad weather we would have arrived on time. 若不是天气坏，我们就准时到达了。
  【注】
  ① 若条件从句为否定句，否定词not应置于主语之后，而不能与were,should,had 等缩略成Weren’t,Shouldn’t,Hadn’t而置于句首。
  ② 有时省略if后提前的had不是助动词：
  Had I time,I would come. 假若我有时间，我会来的。(=If I had time…)
  
  2.省略主语和动词be
  若主从句主语一致，且谓语部分包含有动词be，通常可将主语和动词be省略：
  If repaired earlier,the tractor would not have broken down.
  要是早点儿修一下，拖拉机就不会抛锚了。(=If it had been repaired earlier…)
  
  3.省略“it+be”
  If necessary,I would send more farmhands to help you.
  如果需要的话，我会派更多的人去帮你。(=If it was necessary,…)
  
  4.省略条件从句
  这样的省略通常需要借助一定的上下文，即省略条件从句后，所剩下的主句的意思在一定的上下文中意思是清楚的：
  I might see her personally. It would be better.
  我可以亲自去看她，这样好一些。(=If I saw her personally,it would be better.)
  
  含蓄条件句中
  (1) 条件暗含在短语中。如：
  We didn’t know his telephone number; otherwise we would have telephoned him.
  我们不知道他的电话号码，否则我们就会给他打电话。（暗含条件是otherwise）
  Without your help,we wouldn’t have achieved so much.
  没有你的帮助，我们不可能取得这么大的成绩。
  （暗含条件是介词短语without your help）
  But for your help,I would not have succeeded in the experiment.
  如果没有你的帮助，我的实验就不会成功。（暗含条件是but for your help）
  It would cause great trouble not to lubricate the bearing immediately.
  不立即润滑轴承就会引起很大的故障。
  （暗含条件是not to lubricate the bearing immediately）
  (2) 条件暗含在上下文中。如：
  I would not have done it that way.
  我是不会那么做的。（可能暗含if I were you）
  I was busy that day. Otherwise I would have come to help you.
  我那天很忙。否则我会来帮你的。（可能暗含if I hadn’t been so busy.）
  You might come to join us in the discussion.
  你可以参加我们的讨论。（可能暗含if you wanted to）
  I would have bought the DVD player.
  我是会买下那台影碟机的。（可能暗含if I had the money）
  But for the storm,we should have arrived earlier.
  要不是碰到暴雨，我们还会早些到。（可能暗含if it had not been for the storm）。

• 条件状语从句用法及动词形式:
  1、表示与现在事实相反的情况：
  从句：If 主语+过去时(Be动词用were)
  主句：主语+should/would/could/might+do
  eg：　
  1．If I were you,I would take an umbrella.
  如果我是你，我会带把伞。（事实：我不可能是你）
  2．If I knew his telephone number,I would tell you.
  如果我知道他的电话号码，我就会告诉你。（事实：不知道）
  3．If there were no air or water,there would be no living things on the earth.