What would you do

c  were, would prevent  d  were, would have prevented
3) i __________ if she _________ me.
a  would have overslept ,  didn’t call   b  would have overslept, hadn’t called 
c  overslept, hadn't called    d  would overslept, didn’t call
4) ---- if he ________, he ________that food.
-----luckily he was sent to the hospital immediately.
a  was warned, would not take  b  had been warned, would not have taken
c  would be warned, had not taken  d  would have been warned, had not taken
5) she _______ to the party if she _______ invited.
a  would have gone, had been   b  would go  , was
c  would have gone, was   d  has gone
key:  dabba
3.與將來事實相反
例：1） if i were to be twenty years old, i would take the course of computer science.
       = i would take the course of computer science if i were to be twenty years old, but i am
         not twenty years old, so i will not take the course of computer science.
2) if i did /should do/were to do that , she would feel very surprised.
     =  she would feel very surprised if i did/should do/were to do that, but i don’t do that, so
     she will not feel surprised.
3) if i failed, i would try again.
  = i would try again if i failed, but if i doesn’t fail, i will not try again.
題例：
1) it’s quite impossible that it will rain tomorrow. but if it _________, i would still go to the park.
a  should rain  b  would rain  c  rained  d  had rained
2) i don’t think that i shall fail. but if i _______, i would try again.
a  should fail   b would fail  c  failed  d  had failed
3) ________ tomorrow, what should we do?
a  if it rains  b. should it rain  c. would it rain  d. were it raining
key: aab
注：書面語中，“if”虛擬語氣倒裝形式的使用：
 如果“if”從句中含有 “were, had  ”或“should  ”時， 則可省略連詞“if  ”，而把“were, had ” 或“should” 移至主語之前。
例：
1) were i you (=i were you ), i would ….
2) had they not come last time (=if they had not come last time), we would have done….
3) should it rain tomorrow (= if it should rain tomorrow), she would …
注:
1.某些動詞后賓語從句中的虛擬語氣。
在動詞 suggest, insist, order, command, require, request , demand 等后面的賓語從句中， 動詞形式一般用 “should + 動詞原形，或省略should用動詞原形，用以表示一種建議，勸說， 命令， 要求的語氣。