1. As usual, he put on a show as though his trip______ a great success.
A. had been B. has been C. were D. was
2. Looking round the town, he felt as though he ______ away for ages.
A. has been B. was C. is D. had been
3. John is so strongly built that he looks as if he ______ as elephant.
A. lifts B. is lifting C. lifted D. could lift
4. He described the town as if he ______ it himself.
A. had seen B. has seen C. saw D. sees
5. Most insurance agents would rather you______ anything about collecting claims until they investigate the situation.
A. do B. don’t C. didn’t D. didn’t do
解析：(D)would rather后接从句要求用虚拟语气，形式为过去式，表示对现在或将来的假设，或为过去完成式表示对过去的情况的假设。6. Although most adopted persons want the right to know who their natural parents are, some who have found them wish that they ______ the experience of meeting.
A. hadn’t B. didn’t have had C. hadn’t had D. hadn’t have
7. Without electronic computers, much of today’s advanced technology ______ .
A. will not have been achieved B. have not been achieved
C. would not have been achieved D. had not been achieved
解析：(C)这是一人含蓄虚拟条件句，通过介词短语without,表示潜在的一种假设，而主句中的情况也早已经发生，所以是对过去情况的一种假设，因此用would not have been achieved这一形式。
8. He told her to return the book in time so that others ______ a chance to read it .
A. may have B. will have C. would have D. might have
9. It is time that the government ______ measures to protect the rare birds and animals.
A. takes B. took C. has taken D. taking
解析：(B)It is time that是一种要求从句用虚拟语气的常见句型。虚拟语气形式为动词的过去式。
10. He was very busy yesterday, otherwise he ______ to the meeting.
A. would come B. came C. would have come D. had come
解析：(C)otherwise用来表示一种含蓄的虚拟假设，因为是对过去(yesterday)的情况的假设，所以应该用would have come形式。
If Peter had applied for the post, he would probably get it now.
If he had left for Shanghai yesterday, he would get there now.
与过去事实相反 wish that 从句的谓语动词用had done
与现在事实相反 wish that 从句的谓语动词用did
与将来事实相反 wish that 从句的谓语动词用would/could do
I wish they would change the menu.
I wish I hadn’t spent so much money.
同样地，在as if/as though引导的宾语从句中和以if only引导的带有感叹色彩的虚拟语气句子中，谓语动词与wish引导的宾语从句中的虚拟形式相同。
2. 由if only 引导的虚拟语气
与过去事实相反 if only 谓语动词用had done
与现在事实相反 if only 谓语动词用did
If only she had asked someone’s advice!
3. 由as if/as though 引导的虚拟语气
与过去事实相反 as if/as though谓语动词用had done
与现在事实相反 as if/as though谓语动词用did
He talks about Rome as if he had been there himself.
He orders me as though I were his wife.
1. 表示建议、命令、劝告、决心等主观色彩的动词 + that + (should)+ 动词原形，其中should经常被省略。这类动词包括：advise，ask，command，decide，demand，desire，determine， direct，insist，maintain，move(动议，规定)，order，prefer，propose，recommend，require，stipulate，suggest等等。例如：
It is politely requested by the hotel management that radios (should) not be played after 11 o'clock at night.
2. 以上动词转化为名词，如suggestion，proposal，demand，order，command，advice，desire，requirement，request，agreement，determination，preference，resolution，indication，后接同位语从句或表语从句时，从句要求用虚拟语气，其谓语部分用should + 动词原形，should可以省略。例如：
We are all for your proposal that discussion should be put off.
When the son suggested that they should go to park onSunday, the expression on his father suggested that he agreed with him.
The boy insisted that he didn’t cheat in the exam.
The boy insisted that he shouldn’t cheat in the exam.
4.It is/was + 形容词/过去分词 + that + (should) + 动词原形，这些形容词主要表示必要性、重要性、强制性、合适性、义务性，即某人对某事的反应。这类词包括：important，natural，desirable，possible，astonishing，advisable，anxious，appropriate，compulsory，crucial，eager，essential，fitting，imperative，improper，necessary，obligatory，preferable，proper，urgent，vital，shocked，requested，amazing，strange，odd，ridiculous，surprising，unthinkable，incredible等等。例如：
It is important that students graduating from universities should have not only theory but also practice.
It is surprising that they should kill the time like that.