什么叫定语从句和倒装

定语从句（Attributive Clauses）在句中做定语，修饰一个名词或代词，被修饰的名词,词组或代词即先行词。定语从句通常出现在先行词之后，由关系词（关系代词或关系副词）引出。
关系代词有：who, whom, whose, that, which等。
关系副词有：when, where, why等。

倒装句之全部倒装

全部倒装是只将句子中的谓语动词全部置于主语之前。此结构通常只用与一般现在时和 一般过去时。常见的结构有：
1) here, there, now, then, thus等副词置于句首, 谓语动词常用be, come, go, lie, run。
There goes the bell.
Then came the chairman.
Here is your letter.

2) 表示运动方向的副词或地点状语置于句首，谓语表示运动的动词。
Out rushed a missile from under the bomber.
Ahead sat an old woman.

注意：上述全部倒装的句型结构的主语必须是名词，如果主语是人称代词则不能完全倒装。
Here he comes. Away they went

倒装句之部分倒装

部分倒装是指将谓语的一部分如助动词或情态倒装至主语之前。如果句中的谓语没有助动词或情态动词，则需添加助动词do, does或did，并将其置于主语之前。

1) 句首为否定或半否定的词语，如no, not, never, seldom, little, hardly, at no time, in no way, not until… 等。
Never have I seen such a performance.
Nowhere will you find the answer to this question.
Not until the child fell asleep did the mother leave the room.
当Not until引出主从复合句，主句倒装，从句不倒装。

注意： 如否定词不在句首不倒装。
I have never seen such a performance.
The mother didn't leave the room until the child fell asleep.

以否定词开头作部分倒装

如 Not only…but also, Hardly/Scarcely…when, No sooner… than
Not only did he refuse the gift, he also severely criticized the sender.
Hardly had she gone out when a student came to visit her.
No sooner had she gone out than a student came to visit her.

注意：只有当Not only… but also连接两个分句时，才在第一个分句用倒装结构。如果置于句首的Not only… but also仅连接两个并列词语，不可用倒装结构。
Not only you but also I am fond of music.

so, neither, nor作部分倒装

表示"也"、"也不" 的句子要部分倒装。
Tom can speak French. So can Jack.
If you won't go, neither will I.

注意： 当so引出的句子用以对上文内容加以证实或肯定时，不可用倒装结构。意为"的确如此"。
Tom asked me to go to play football and so I did.
---It's raining hard. ---So it is.

only在句首要倒装的情况

Only in this way, can you learn English well.
Only after being asked three times did he come to the meeting.
如果句子为主从复合句，则主句倒装，从句不倒装
Only when he is seriously ill, does he ever stay in bed.

as, though 引导的倒装句

as / though引导的让步从句必须将表语或状语提前 （形容词, 副词, 分词, 实义动词提前）。

注意：
1) 句首名词不能带任何冠词。
2) 句首是实义动词, 其他助动词放在主语后。如果实义动词有宾语和状语, 随实义动词一起放在主语之前。
Try hard as he will, he never seems able to do the work satisfactorily.

注意:
让步状语从句中，有though，although时，后面的主句不能有but，但是 though 和yet可连用。

其他部分倒装

1) so… that 句型中的so 位于句首时，需倒装。
So frightened was he that he did not dare to move an inch.

2) 在某些表示祝愿的句型中：
May you all be happy.

3) 在虚拟语气条件句中从句谓语动词有were, had, should等词，可将if 省略，把 were, had, should 移到主语之前，采取部分倒装。
Were I you, I would try it again.

1. 定语从句，一个简单句跟在一名词或代词后（先行词）进行修饰限定，所以叫做定语从句。在主句中充当定语成分。

2. 被修饰的词叫先行词。定语从句不同于单词作定语的情况，它需要放在被修饰的词（即先行词）之后。定语 从句由关系词（关系代词、关系副词）引导，关系代词、关系副词位于定语从句句首。
   

3. 为了强调、突出等语的目的而颠倒原有语序的句式叫做倒装句。在倒装句中，颠倒了的成分可以恢复原位而句意基本不变，句法成分不变。

4. 也叫谓语前置或主语后置。古汉语中。谓语的位置也和现代汉语中一样，一般放在主语之后，但有时为了强调和突出谓语的意义，在一些疑问句或感叹句中，就把谓语提前到主语前面。