概述
独立主格结构是由一个相当于主语的名词或代词加上非谓语动词、形容词(副)词、或介词短语构成的一种独立成分。该结构不是句子，也不是从句，所以它内部的动词不能考虑其时态、人称和数的变化，它与其主句之间既不能通过并列连词连接也不能有从句引导词引导，常用逗号与其主句隔开。独立主格结构在很多情况下可以转化为相应的状语从句或其他状语形式，但很多时候不能转化为分词形式，因为它内部动词的逻辑主语与主句主语不一致。在做这类题目时一定要小心判断，不能粗心大意。

构成形式

独立主格结构的构成方式为：名词普通格或代词主格+现在分词／过去分词／不定式／名词／形容词／副词／介词短语等。使用独立主格结构是因为出现了与句子主语不一致的情况

1． 名词或代词+现在分词
现在分词表示前面的名词或代词主动进行的动作或状态。如：
The man lay there, his hands trembling.
那个男子躺在那儿，双手在颤抖。
有时，现在分词being或having been在独立主格结构中可以省略。如：
The weather (being) fine,we decided to go swimming.
天气晴朗，我们决定去游泳。

2． 名词或代词＋过去分词
过去分词表示前面的名词或代词被动完成的动作。

如：
The girl sat there silent,her head bent low.
这姑娘一声不响，低着头坐在那里。

All things considered, her paper is of greater value than yours.
各方面考虑起来，她的论文比你的论文更要有价值一些。

3． 名词或代词+不定式（短语）
不定式表示将来的动作。

如：
He suggested going for a picnic,Mary to provide the food.
他建议去野餐，由玛丽负责提供食物。

Time is pressing, two hours to go only.
时间紧迫，只剩两个小时了。

4． 名词或代词+名词(短语)

如：
Many people joined in the work, some of them women and children.
许多人参加了这项工作，其中一些人是妇女和儿童。

5． 名词或代词+形容词(短语)
形容词(短语)说明前面名词或代词的性质或状态。

如：
The floor wet, we had to stay outside for a while.
地面很湿，我们只好在外面呆一会儿。

6． 名词或代词+副词
副词也多是说明前面名词或代词的状态。

如：
The meeting over, we all went home.
会议结束了，我们都回家了。

7． 名词或代词+介词短语

如：
The teacher came in, a book in his hand.
老师进来了，手里拿着一本书。

8. 有时，独立主格结构中名词前面的定语可以省略。

如：
The boy lay silently on the grass, (his) eyes closed.
A girl was walking in the street, (a) flower in (her) hand.

作用

1． 作状语

1) 表示时间 如：
Her homework done (=After her homework was done),Lucy decided to go shopping.

2) 表示原因 如：
There being no buses (Because there were no buses),we had to walk home.

3) 表示条件 如：
Weather permitting (If weather permits), we will go to play football.

4) 表示方式或伴随 如：
He rushed into the room, his face covered with sweat.

2． 作同位语 如：

There are two doors, one leading to the bedroom, the other (leading) to the kitchen.

与介词使用

1) 独立主格结构使用介词的问题：

当介词是in时，其前后的两个名词均不加任何成分(如物主代词或冠词)，也不用复数。但 with 的复合结构不受此限制

A robber burst into the room, knife in hand.

( hand前不能加his)。

2) 当表人体部位的词做逻辑主语时，及物动词用现在分词，不及物动词用过去分词。

He lay there, his teeth set, his hand clenched, his eyes looking

straight up.

典型例题：

Weather___, we'll go out for a walk.

A permitted B permitting C permits D for permitting

答案B. 本题中没有连词，它不是复合句，也不是并列句。 句中使用了逗号，且we

小写，可知其不是两个简单句。能够这样使用的只有独立主格或with的复合结构。据此判断，本句中使用的是独立结构， 其结构为：名词+分词。

由于permit在这里翻译为'天气允许'，表主动，应用现在分词，故选B。

如果不会判断独立结构作状语的形式，不妨将句子改为条件句，例如本句改为If weather permits, we'll go out for a

walk. 然后将if 去掉，再将谓语动词改为非谓语动词即可。

专项练习

1．Ford tried dividing the labor，each worker_a separate task．
A．assigning B．assigned C．was assigned D．would be assigned

2．The lecture_，he left his seat so quietly that no one complained that his leaving disturbed the speaker．
A．began B．beginning C．having begun D．being beginning

3．Such_the case ，there are no grounds to justify your complaints．
A．being B．is C．was D．to be

4．Darkness_ in，the young people lingered on merrymaking．
A．set B．setting C．has set D．was set

5．With all factors_，we think this program may excel all the others in achieving the goal．
A．being considered B．considering C．considered D．are considered

6．A new technique_，the yields as a whole increased by 20 percent．
A．to have been worked out B．having worked out C．working out D．having been worked out

7．On the top was the clear outline of a great wolf sitting still，ears ，alert，listening．
A．pointed B．pointing C．are pointed D．are pointing

8．Walter offered us a lift when he was leaving the office ，but our work_，we declined the offer．
A．not being finished B．not having finished C．had not been finished D．was not finished

9．There are various kinds of metals ，each its own properties．
A．has B．had C．to have D．having

10．The article opens and closes with descriptions of two news reports，each_one major point in contrast with the other．
A．makes B．made C．is to make D．making

Key：1—5 BCABC 6—10 DAADD