谁能帮我答一下和英语语言学有关的问题,要英语回答,急用!The following two excerpts are taken from an article (VAN DIJK:Context and Cognition:Knowledge Frames and Speech Act Comprehension).In one place,the author writes:This pape

谁能帮我答一下和英语语言学有关的问题,要英语回答,急用!The following two excerpts are taken from an article (VAN DIJK:Context and Cognition:Knowledge Frames and Speech Act Comprehension).In one place,the author writes:This pape
谁能帮我答一下和英语语言学有关的问题,要英语回答,急用!
The following two excerpts are taken from an article (VAN DIJK:Context and Cognition:Knowledge Frames and Speech Act Comprehension).In one place,the author writes:
This paper is intended as an introductory survey of some problems in the interdisciplinary domain of pragmatics and cognitive psychology.…I am indebted to Walter Kintsch for some helpful suggestions concerning this paper and for his permanent advice and collaboration in our work on discourse processing in general.
And in another,he writes:
As we will briefly mention below,conventions are involved,where conventions are taken as strictly objective properties of social structure.
How do you account for the difference in the use of person deictic expressions (I in the first part and we in the second),i.e.in the first the writer uses I,and in the second,he uses we?

谁能帮我答一下和英语语言学有关的问题,要英语回答,急用!The following two excerpts are taken from an article (VAN DIJK:Context and Cognition:Knowledge Frames and Speech Act Comprehension).In one place,the author writes:This pape
以下两个片断是从一篇文章（文迪克：语境与认知：知识框架和言语行为理解） .在一个地方,作者写道：
本文的目的是作为一个介绍性的调查中若干问题的跨学科领域的语用学和认知心理学....我很感激华克印赤的一些有用的建议有关这个文件和他的常任理事国的意见和协作,我们在工作中处理话语一般.
在另,他写道：
正如我们将简短地提及以下,参与公约,在公约是采取严格的客观性质的社会结构.
你怎么到的差异在使用人的指示表达（我的第一部分,我们在第二） ,即在第一作者利用我,并在第二,他利用我们?

In the first part the author uses I to express his individual gratitude to Walter Kintsch, this usage implies his identity as an individual.Whereas he uses we in another to acknowledge others's efforts, this useage implies that he does not attribute this piece of work as his own,but an achivement that belongs to all concerned.