Abstract
In daily commuicative activities, address forms are usually the first information that the addressor conveys to the addressee aiming at establishing a certain social relationship between the two speakers. Code switching, the alternations of linguistic varieties within the same conversation, is a universal phenomenon in communication. Theories on code switching can be employed in the analysis of address form switching. To investigate this intriguing topic, the thesis adopts Gumperz’s theory and classifies address form switching into situational address form switching and metaphorical address form switching. Through the careful observation and analysis of the examples, the present thesis has shed some light on the factors affecting people to change the address forms under the different situations.
Keywords  situational address form switching  metaphorical address form switching motivation
 
在言语交际过程中，对同一对象使用的称呼并不是一成不变的，称呼语随着场合、交际者角色关系以及话题的改变而不断发生变化，它也能改变话题、交际的氛围并调节人际关系，重建当前情景，从而实现说话者的社会心理动机。称呼语也属于语码的一种，它的转换也受到语码转换规律的支配，本文主要研究在不同的情景下，影响人们使用不同称呼语的因素。根据Gumperz对语码转换的分类，称呼语的转换可分为情景式称呼语转换和喻意式称呼语转换。情景式称呼语转换主要是指由言语外因素如时间、地点、话题等影响下的称呼语的转换，喻意式称呼语转换一般是指说话者意图改变话题、交际的气氛或者调节人际关系而进行的称呼语的转变。
关键词  情景型称呼语转换  寓意型称呼语转换  心理动机

1 Introduction
In daily communicative activities, address forms play a vital role in human communication. Adress forms are the first information that the addressor passes on to the addressee in order to estabilish the certain social relationship. The addressor, as the main body of sociality, selects address forms according to the addressee's age, occupation, status, identity and seniority, and also on the basis of the degree of closeness and intimacy between two speakers, the situation at that time, and many other factors. Different address forms not only reflect the role of both sides, status and the degree of closeness, but also can express the attitudes and feelings of one side to the other side. The appropiate adress forms will ensure the smooth communication; otherwise, there will be a communicative obstacle which harms the normal sociality between the speakers.