副詞提至句首引起倒裝，可分以下幾種情況：
1、only + 副詞（when，before，if，after等）或only+介詞狀語（由in，under，by，on，after等引導(dǎo)）提前，必須部分倒裝。
如：Only then did he realize how stupid he had been.
Only after entering the store did Arthur realize that there was dan ger.
Only in the library can she concentrate on her study.
2、often，such，so等副詞提前，部分倒裝。
如：So diligently did he work that he got hight scores on the final exam. =He worked so diligently that he got hight scores on the final exam.
Such was his wish that the world would stay away from war forever.
Often did we go on a holiday in hot summer. 注意，so的另一種倒裝是表示“也…”。
California relies heavily on income from crops，and so does Florida. 加利福尼亞過多的依賴于來自農(nóng)作物的收入，佛羅里達(dá)也是這樣同理，體會(huì)一下neither，nor的倒裝。
He can't dance，neither/nor can I.= I can't，either.
他不會(huì)跳舞，我也不會(huì)。
3、in，out，down，up，away，off，here，there，over等副詞提前，全部倒裝。
如：Off got the staggering gentlemen.
Here are the photos I took at the seaside.
疑問句需部分倒裝語序，由于經(jīng)常用到不會(huì)成為考試的難點(diǎn)。
如：What part did he play in Hamlet？
Do you prefer tea or coffee？
by可視為被動(dòng)語態(tài)的標(biāo)志詞，by之后的名詞短語是句中動(dòng)作的施動(dòng)者；在題干中若見到by+名詞的結(jié)構(gòu)要優(yōu)先考慮用被動(dòng)式
如：The wall is painted by Tom.
The book was written by Mark Twain.
注意1：by之后如果接的是動(dòng)名詞，則表示方式、手段，不能視為被動(dòng)式的標(biāo)志，且此時(shí)謂語應(yīng)用主動(dòng)式，如：He passed the exam by cheating.
注意2：對(duì)于know來講，一般用be known to而不用be know by強(qiáng)調(diào)句中it作形式主語可以替代任何被強(qiáng)調(diào)的部分基本模式：It + be + 強(qiáng)調(diào)對(duì)象+ who/ whom/that + 句子其余部分。
如：It was only you who cared for me. （強(qiáng)調(diào)主語）
It is his sister whom /that I have fallen in love with. （強(qiáng)調(diào)賓語）
It was under the tree that she found her missing purse. （強(qiáng)調(diào)地點(diǎn)狀語）
It was last week that I attended an art exhibit for the first time. （強(qiáng)狀語）
It was not until he broke my favorite vase that I flew into rages. （強(qiáng)調(diào)狀語從句）
注意：強(qiáng)調(diào)的對(duì)象是人時(shí)，可用who，whom或that，其余情況一律用that；當(dāng)強(qiáng)調(diào)對(duì)象在從句中做主語時(shí)用who/that，當(dāng)強(qiáng)調(diào)對(duì)象在從句中做賓語時(shí)用whom/that。
虛擬語氣
此章內(nèi)容在TOEFL考點(diǎn)中處于相對(duì)次要地位，但在英文中是比較活躍的用法，必須對(duì)其有所了解，這樣對(duì)讀題非常有幫助虛擬語氣是英文中一特殊的語言現(xiàn)象，主要用于表達(dá)與事實(shí)相反的陳述，常表達(dá)強(qiáng)烈愿望、遺憾、感慨、后悔、責(zé)備、規(guī)勸等語義，可大致分為三類。
對(duì)現(xiàn)在事實(shí)的虛擬基本形式：If + were /did等過去式…，…would /could /should /might + do
例如：If I were a bird，I would fly to the moon.
（事實(shí)上，I' not a bird，so I will not fly to the moon.）
If she knew who you are，she would go out of joy.
1、only + 副詞（when，before，if，after等）或only+介詞狀語（由in，under，by，on，after等引導(dǎo)）提前，必須部分倒裝。
如：Only then did he realize how stupid he had been.
Only after entering the store did Arthur realize that there was dan ger.
Only in the library can she concentrate on her study.
2、often，such，so等副詞提前，部分倒裝。
如：So diligently did he work that he got hight scores on the final exam. =He worked so diligently that he got hight scores on the final exam.
Such was his wish that the world would stay away from war forever.
Often did we go on a holiday in hot summer. 注意，so的另一種倒裝是表示“也…”。
California relies heavily on income from crops，and so does Florida. 加利福尼亞過多的依賴于來自農(nóng)作物的收入，佛羅里達(dá)也是這樣同理，體會(huì)一下neither，nor的倒裝。
He can't dance，neither/nor can I.= I can't，either.
他不會(huì)跳舞，我也不會(huì)。
3、in，out，down，up，away，off，here，there，over等副詞提前，全部倒裝。
如：Off got the staggering gentlemen.
Here are the photos I took at the seaside.
疑問句需部分倒裝語序，由于經(jīng)常用到不會(huì)成為考試的難點(diǎn)。
如：What part did he play in Hamlet？
Do you prefer tea or coffee？
by可視為被動(dòng)語態(tài)的標(biāo)志詞，by之后的名詞短語是句中動(dòng)作的施動(dòng)者；在題干中若見到by+名詞的結(jié)構(gòu)要優(yōu)先考慮用被動(dòng)式
如：The wall is painted by Tom.
The book was written by Mark Twain.
注意1：by之后如果接的是動(dòng)名詞，則表示方式、手段，不能視為被動(dòng)式的標(biāo)志，且此時(shí)謂語應(yīng)用主動(dòng)式，如：He passed the exam by cheating.
注意2：對(duì)于know來講，一般用be known to而不用be know by強(qiáng)調(diào)句中it作形式主語可以替代任何被強(qiáng)調(diào)的部分基本模式：It + be + 強(qiáng)調(diào)對(duì)象+ who/ whom/that + 句子其余部分。
如：It was only you who cared for me. （強(qiáng)調(diào)主語）
It is his sister whom /that I have fallen in love with. （強(qiáng)調(diào)賓語）
It was under the tree that she found her missing purse. （強(qiáng)調(diào)地點(diǎn)狀語）
It was last week that I attended an art exhibit for the first time. （強(qiáng)狀語）
It was not until he broke my favorite vase that I flew into rages. （強(qiáng)調(diào)狀語從句）
注意：強(qiáng)調(diào)的對(duì)象是人時(shí)，可用who，whom或that，其余情況一律用that；當(dāng)強(qiáng)調(diào)對(duì)象在從句中做主語時(shí)用who/that，當(dāng)強(qiáng)調(diào)對(duì)象在從句中做賓語時(shí)用whom/that。
虛擬語氣
此章內(nèi)容在TOEFL考點(diǎn)中處于相對(duì)次要地位，但在英文中是比較活躍的用法，必須對(duì)其有所了解，這樣對(duì)讀題非常有幫助虛擬語氣是英文中一特殊的語言現(xiàn)象，主要用于表達(dá)與事實(shí)相反的陳述，常表達(dá)強(qiáng)烈愿望、遺憾、感慨、后悔、責(zé)備、規(guī)勸等語義，可大致分為三類。
對(duì)現(xiàn)在事實(shí)的虛擬基本形式：If + were /did等過去式…，…would /could /should /might + do
例如：If I were a bird，I would fly to the moon.
（事實(shí)上，I' not a bird，so I will not fly to the moon.）
If she knew who you are，she would go out of joy.