If the United States had built more homes for poor people in 1955，the housing problems now in some parts of this country ___ so serious.
［A］ wouldn’t be ［B］ will not have been ［C］ wouldn’t have been ［D］ would have not been
homework ［C］ If Mike could finish his homewor ［D］ If Mike had been able to finish his
homework
3) If the United States had not entered the Second World War，probably the 1940 unemployment rate of 14％ ___still further.
注意： 如suggest, insist不表示"建议" 或"坚持要 某人做某事时"，即它们用于其本意"暗示、表明"、 "坚持认为"时，宾语从句用陈述语气。 The guard at gate insisted that everybody obey the rules.
eg: It is suggested that we (should) hold a meeting next week.
eg: It is necessary that he (should) come to our meeting tomorrow.
2）在宾语从句中的应用 在表示命令、建议、要求等一类动词后面的从句中。
［A］ If he has listened to me ［B］ Had he listened to me ［C］ If he listened to me ［D］ As soon as he listened to me
特殊的虚拟语气词：should
1） It is demanded / necessary / a pity + that…结构中的主语从句的谓语动词要用 should 加动词原形， should 可省略。
almost all of the world’s supply.
diamonds would have not
3. 与将来的事实相反
5) It is said Tom will go to an appointment tommorrow. If he were to come tomorrow, I ___ ask him to go to your place.
虚拟语气
Subjunctive mood
真实条件句
真实条件句用于陈述语气，假设的情况可 能发生，其中 if 是如果的意思。
时态关系
句型： 条件从句
主句
一般现在时 shall/will + 动词原形
If he comes, he will bring his violin.
真实条件句
典型例题 The volleyball match will be put off if it ___.
If you were to succeed, everything would be all right.
1. 与现在的事实相反
1) What type of automobile would you buy ___ ? ［A］ if you have free choice to choose the cars
should/would have + done (过去分词）
should/would + 动 词原形
a. 同现在事实相反的假设。
句型 ：
条件从句
主句
一般过去时
should( would) +动词原
If they were here, they would help you.
b. 表示于过去事实相反假设。
If I were you, I would go to look for him. 如果我是你，就会去找他。
If he were here, everything would be all
right. 如果他在这儿，一切都会好的。
典型例题 _____ to do the work, I should do it some
shall (will) +动词原形，而直接用一般现在 时的动词形式。
非真实条件句
时态：可以表示过去，现在和将来的情况。它的 基本特点是时态退后。
条件从句
主句
同现在事实相反 同过去事实相反 同将来事实相反
一般过去时
过去完成时
一般过去时 were + 不定式 should + 动词原形
should/would + 动 词原形
A. will rain B. rains C. rained D. is rained
注意： 1） 在真实条件句中，主句不能用be going to表示将来，该用shall, will.
If you leave now, you are never going to
regret it.
If you leave now, you will never regret it. 2） 表示真理时，主句谓语动词便不用
句型：
条件从句 过去完成时
主句 should(would) have+ 过去分
If she had worked harder, she would have
succeeded.
The rice would not have been burnt if you had
been more careful.
If my lawyer had been here last Saturday, he
would have prevented me from going.
If he had come yesterday, I should / would have told him about it.
虚拟条件句的倒装
虚拟条件句的从句部分如果含有were, should, 或 had, 可将if省略，再把were, should或had 移到从 句句首，实行倒装。
If they were here now, they could help us. =Were they here now, they could help us. Had you come earlier, you would have met him. =If you had come earlier, you would have met
含义：He did not come yesterday, so I did not tell him about it.
If he had not been ill and missed many classes, he would have made greater progress.
含义： He was ill and missed many lessons, so he did not make greater progress.
［A］ would rise
［B］ would risen
［C］ would have risen
［D］ had risen
4) Top grade ［A］ diamonds had not ［B］ increased so sharply ［C］ in value in the late seventies ［D］ if one company had not controlled
If you had asked him yesterday, you would know what to do now. （从句与过去事实相反，主句与现在事实相反。）
If it had rained last night (过去), it would be very cold today (现在).
cars available today
2. 与过去的事实相反(有时主句中的should have done表示责备或后悔)
2) ___ he would have come to class. ［A］If Mike is able to finish his homework ［B］Would Mike be able to finish his
order, suggest, propose, require, demand, request, insist, command, insist + (should) do eg: I suggest that we (should) hold a meeting next week.
He insisted that he (should ) be sent there.
c. 表示对将来的假想
句型： 条件从句 一般过去时 were+ 不定式 should+ 动词原形
主句 should+ 动词原形 would + 动词原形
If you succeeded, everything would be all right.
If you should succeed, everything would be all right.
him. Should it rain, the crops would be saved =If it should rain, the crops would be saved.