名词性从句中的虚拟
主语从句(it is +adj./p.p that)
同位语从句(The +n. That)
表语从句(n. +be that)
省略if 的虚拟法（倒装）(1)
虚拟语气中如果从句引导词if / whether 省略，从句中需要倒装，提前助动词(系动词）或情态动词。
< If it should rain tomorrow, we would not be able to have the sports meeting.
=Should it rain tomorrow, we should not be able to have the sports meeting.
省略if 的虚拟法（倒装）(2)
< whether it (may) be fine or rainy, we would have the sports meeting.
=Be it fine or rainy, we would have the sports meeting.
If she had been given more information, she could have answered the questions.
=Had she been given more information, she could have answered the questions.
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总结虚拟语气的动词标志
"insist, suggest, require, request, demand, propo, prefer, maintain, move, urge, recommend, command, order"等动词表"建议、愿望"时，其后宾语从句中谓语动词要用虚拟语气。Should +V
wish其后宾语从句中谓语动词要用虚拟语气。{
虚拟语气的名词标志
1 “necessity”或“suggestion”等名词后面的表语从句或同位语从句中的谓语动词要用虚拟语气。
2 名词word 表“命令”时，其后主语从句、表语从句或同位语从句中，谓语动词需用虚拟语气(should)+V。
3 wish 作名词时其后主语从句，表语从句或同位语从句中，谓语动词需用虚拟语气(should)+V。
虚拟语气的形容词标志galumb
It is + adj. that 句型中出现形容词如necessary, important, vital, decisive, critical, crucial, urgent, strange, desirable, advisable, disappointing, 或过去分词充当的形容词如suggested, propod, advid, demanded, requested, required等时，that 句中用s h o u l d+V表示虚拟。
sub是什么意思
虚拟的介词标志
But for相当于if it had not been for。But for her help, I would have lost my way. Without, in the abnce of 等组成的短语可相当于一个虚拟的条件从句。Without the light and heat of the sun, what would become of all the animals on earth? In the abnce of water, plants would not
grow well.
Under…condition，也可相当于一个虚拟条件从句。
Under more favorable conditions, we would have made more achievements.
错综时间的虚拟
条件状语从句中谓语动词的形式可与主句中谓语动词的形式不“配套”，即错综时间的虚拟。
If he had done as I had suggested then, he wouldn’t be regretful now.
If they hadn’t found us then, we would still be missing on the a. If I hadn’t made sufficient preparation for the exam then, I wouldn’t be in college now.
虚拟和事实
（前虚拟后事实）标志: but E.g. I would have gone to the party with you, but I was too busy.
= If I hadn’t been too busy, I would have gone to the party with you.
（前事实后虚拟）标志: otherwi E.g. I was too busy then, otherwi I would have gone to the party with you.
More Information
was (were) +to have done （不定式完成式）表示“原来想做而未做”后面通常but…（陈述语气）。
< I was to have arrived home on time, but my car was held up by a bad traffic jam. had hoped表示过去未实现的愿望，其从句中谓语动词要用虚拟would+V。
< I had hoped that he would agree to lend me the money.
(倒装）
带否定意义的副词置于句首时(1)
带否定意义的词置于句首时，主谓语需要倒装。
Rarely does he go to the movies.
Not for a moment did he doubt the truth of her honesty.
Little do I know about the meaning of this proverb?
Never before the night had I felt the extent of my power.
含有否定词的介词短语在句首
含有否定词的介词短语在句首时，句子主谓倒装。
这类介词短语包括：in no ca, at no time, in no way, by no means, on no account, in no n, under no circumstances, 等等。意思为“决不，在任何情况下都不。”“Only+状语”置于句首时的倒装(1)
“Only+状语”置于句首时，主谓语需要倒装。
1) Only by practicing a lot outside class can we speak English fluently.
2) Only when I saw him did I remember that I promid to bring him a gift.
3) Only then did I know that I was wrong.
not only位于句首时的倒装
句首是not only且连接分句结构时，引起局部（部分）倒装。
Not only did we lo our money, but we were also in danger of losing our lives.
Not only can he sing very well, but he can also play some musical instrument very skillfully.
neither，nor表示“也不”时的倒装
(1)
句首是neither，nor表示“也不”时，主谓语需要倒装。
I couldn’t solve the problem, neither /nor could my brother.
= I couldn’t solve the problem. My brother couldn’t, either.
I didn’t go to school, nor did Mary.
= I didn’t go to school. Mary didn’t, either.
so表示“也是，同样”时的倒装
句首是so表示“也是，同样”时，主谓语需要倒装。
Copper is a good conductor; so is silver.
John failed in the exam; so did Mark.
He takes part in sports activities, so do his classmates.
I have been to the Temple of Heaven, so has she?
平衡倒装
There+be或其它不及物动词come，go，happen，occur，stand，exist等结构中，为避免句子头重脚轻，平衡倒装。
There stands an old hou that is being pulled down.
There existed a hostile relationship between the two families.
There are many hobbies involving the creativity of a person.
Such/so…that句型中的倒装
Such/so…that句型中such+名词或so+形容词，副词等位于句首时，主句中主谓倒装。So badly was he injured in the accident that he had to stay in the hospital for treatment? So excited was I that I didn’t know what to say.
比较状语从句中的倒装
than引导的比较状语从句中，主从句谓语趋向中间以达到平衡，此时从句要求主谓倒装。
Nowadays, with the rapid development of science and technology, man is less limited by nature than were his forefathers/ancestors.
表频率的状语至于句首倒装
谷歌词典
表频率的状语至于句首，倒装。
Many a time has he given us sound advice?
Twice a week does he go to visit his grandparents?
More than once have we heard him make such promis?
As, though让步状语从句中倒装
在以as，though引导的让步状语从句中，从句常用倒装语序，把表语或状语提前。（名，形，付，动词）
Child that he is, he can distinguish between right and wrong.
Intelligent as/though you are, you should be modest.
Much as I admire him, I don’t think he is perfect.
Try as she did, she failed again.
虚拟语气中的倒装
虚拟语气中省略“i f”或“w h e t h e r”时的倒装。
Was it left to me to choo, I prefer the latter to the former.
Had it not rained so heavily, we would have visited the Summer Palace yesterday?
Be we rich or poor, we should have our own dignity.
焦糖玛奇朵英文副词至于句首
Here、there、in、out、up、down等表示方位的副词至于句首时，主谓需要倒装。Here comes the bus.
Down jumped the little boy from the bridge.
Here it ( 指the bus) comes.
There they went.
就近/毗邻一致原则(1)
There 或here引起的句子中主语不止一个时，谓语就近一致。
就近/毗邻一致原则(2)
由or、either…or 或neither…nor、not only、…but also、not,…But…等连接的两个主语谓语就近一致。
one man show radio mix谓语动词多用单数的情况（1）
Many a /More than one所修饰的名词作主语时谓语动词多用单数。
Many a brave soldier has died in that battle.
More than one question has been raid in the lecture.
谓语动词多用单数的情况（2）
pant suEither/neither做主语通常作单数看待，谓语动词多用单数。
Either of the methods is effective.
autobanNeither of the roads leads to the town.
谓语动词多用单数的情况（4）
主语中包括“and”时，若表示一个单一概念，谓语动词应做单数。加：(and 连接两个单数名词前面如有each、every，many a，no等)
The poet and writer has come.role是什么意思
什么是抑郁症All work and no play makes Jack a dull boy.
Every man and woman is eager to find a life-long companion.
谓语动词多用单数的情况（5）
主语是单数，后面尽管有with、together、with 、along with 、besides 、as well as 等引导的短语，谓语动词仍用单数。
The teacher, together with some of her students, was cleaning the classroom.
