独立主格结构作为一个重要的语法项目，频频出现在近几年的四级考题中。由于中学教材已不把它作为重点，大学教材对它也缺乏系统的阐述，不少考生因此而难以在与之有关的试题上得分，更谈不上在语言实践中加以应用。笔者试图对该结构进行较为全面的分析，以期对考生有所帮助。
I．独立主格的结构形式
独立主格结构在形式上由两部分组成。第一部分由名词或代词担任，第二部分由分词、动词不定式、形容词、副词、名词或介词短语担任，但在四级考试中以分词担任第二部分的居多，有时也会由不定式担任。
1）名词或主格代词＋现在分词
例1，______a man who expresses himself effectively is sure to succeed more rapidly than a man whose command of language is poor．
A）Other things being equal B）Were other things equal C）To be equalto other things D）Other things to be equal
（答案A Band 4，1997．6）
例2 So many directors ______，the board meeting had to be put off．
A）were absent B）been absent C）had been absent D）being absent
（答案D Band 4，2001．1）
当独立主格中的分词所表示的动作先于句中谓语动词所表示的动作时，用分词的完成形式。
例3 The speech______，a lively discussion started． A）being delivered B）was delivered C）be deliveredD）having been delivered
（答案D Band 4，1995．1）
当独立主格结构中的名词或主格代词是分词表示的动作的承受者时，用分词的被动形式。
例4 All flights_____because of the snow-storm，many passengers could do nothing but take the train． A）were canceled B）having been canceled C）had been canceled D）have been canceled
（答案BBand 4，1999．1）
2）名词或主格代词＋过去分词
例5 All things_____，the planed trip will have to be called off．
A）be consideredB）considered C）consideringD）having considered
（答案BBand 4，1998．6）
3）名词或主格代词＋动词不定式
例6 If the building project______by the end of this month is delayed，the construction company will be fined．
A）to be complete B）is completed C）being completedD）complete
（答案A Band 4，2001．6）
形容词、副词、名词和介词短语担当第二部分的情况在四级考试中虽不多见，但在书面语中却是一种有效的表达手段，在此略举几例，供有兴趣的同学参考。
4）名词或主格代词＋形容词
例7 Hands red with the cold，they were sweeping the snow outdoors．（他们在户外扫雪，两手冻得通红。）
5）名词或主格代词＋介词短语
例8 A book in hand，the teacher of English walked into the classroom．（手里拿着本书，英语老师走进教室。）
6）名词或主格代词＋副词
例9 Class over，all students went to play on the playground．（下课了，学生们都到操场上去玩耍。）
7）名词或主格代词＋名词
例10 His first shot failure，he fired again．（他第一枪没击中，又打了第二枪。）
以上三种结构实际上很接近主系表结构，如例8，原应是A book being in hand．．．省略了being，就成了上述结构。
8）介词引导的独立主格结构
上述各项结构形式前面有时可以带有某些介词，从而构成介词引导的独立主格结构。
这类介词主要由with，without，like，on等，限于篇幅，本文仅列举几例，以供参考。
例11 The sale usually takes place outside the house， with the audience____on benches，chairs or boxes． A）having seated B）seating C）seatedD）having been seated
（答案C Band 4，2000．1）
例12 I can't write，with you looking over my shoulder．（因为你趴在我肩上看，所以我没法写。）
例13 Without a word more spoken，they went away．（他们没有再多说一句话，就走开了。）
例14 I told him everything，and he stood and listened，like a figure cut in stone．（我把一切情况都告诉了他，他呆若木鸡，站在那儿倾听。）
例15 On the news being announced，she got so excited that she cried in the public．（听到那个消息，她激动得在大庭广众之下哭了起来。）
II．独立主格结构的句法功能
1．独立主格结构在句中主要用作状语，可表示条件，如例5、例6；表示原因，如例2、例4、例10、例12、例15；表示时间，如例3、例9；表示伴随动作或状况，如例1、例7、例8、例11、例13、例14。
当独立主格结构作条件、原因、时间状语时，实际上相当于相应的状语从句。试比较：
1）All things considered，the planed trip will have to be called off．（例5）
If all things are considered，the planed trip will have to be called off．
2）All flights having been canceled because of the snowstorm，many passengers could do nothing but take the train．（例4）
Because all flights had been canceled because of the snowstorm，many passengers could do nothing but take the train．
3）Class over，all students went to play on the playground．（例9）
When class was over，all students went to play on the playground．
当独立主格结构表示伴随动作或状态时，其功能相当于并列句中的一个分句。试比较：
1）Hands red with cold，they were sweeping the snow outdoors．（例7）
Their hands were red with cold，and they were sweeping the snow outdoors．
2）A book in hand，the teacher of English walked into the classroom．（例8）
The teacher of English walked into the classroom， and a book was in his right／left hand．
2．有时独立主格结构也能用作定语和主语，但在四级范围内尚属罕见，在此略作介绍。
独立主格结构作定语，要放在它所修饰的名词后面，其功能相当于一个定语从句。例如：
- 考试辅导
