Dating back to history, there were three landmarks that had promoted the booming of novel blending words. The word “blending”, evolved from the word “portmanteau”, was first and foremost being used in the context by Lewis Carroll(1971) in the book Through the Looking-Glass such as slithy (lithe+slimy), galumph (gallop+triumph) and chortle (chuckle+snort). Later, the techniques of creating blending words were fully displayed in Ulysses and Finnegans Wake of James Joyce. He used 63924 words in his work Finnegans Wake and created a huge amount of neologism, among which portmanteau word ranked the first.(Dai, 2005:66). He broke the state of isolation between words, thus complex and rich meanings were able to be created. Last but not least, according to a survey on the 3rd edition of LONGMAN Dictionary of Contemporary English, 20.5% of new words were formed through the way of blending, which ranked the second in the total new words formations. (c.f. Cui, 2012:85)

Apart from reasons stated above, some external reasons are also attributed to the increasing amount of novel blending words. For instance, with the change of the political situation, the concept Chidia (China+India) and Chimerica (China+America) reflects the trade cooperation between China and India as well as China and America has been further strengthened. In the field of global economy, people use the word Eurogeddon ( Europe+Armageddon) to describe a very serious financial or military crisis in Europe. When it comes to daily life, the word flexitarian (flexible+vegetarian) was created to describe a certain group of vegetarians who eat meat sometimes in order to seek a balanced nutrition.

To sum up, lexicon is the part of language that most obviously and most rapidly reflects the social changes. As the civilization develops in technical, scientific, cultural and economic way，so does the language, especially the lexicon, which will always follow the trends of social evolution.

2.2 Theoretical Foundation
This thesis aims at using three key theories as the theoretical foundations, namely Conceptual Metaphor Theory (CMT), Conceptual Blending Theory (CBT) and Prototype Theory (PT).

In terms of CMT, with its origins in Lakoff & Johnson (1980), it is one of the central areas of research in the field of cognitive linguistics. Within this field, the notions of “source domains” and “target domains”, “invariance”, “mappings”, and so forth have become a common vocabulary for discussing the linguistic and conceptual phenomena of metaphor (Lakoff & Johnson, 1980:45).The findings and principles of this framework have been applied in numerous studies, both within and outside of the field of linguistics.

Later, a more recent framework, proposed by Fauconnier and Turner (1994; 1998) seeks to explain much of the same linguistic data, and also to unify the analysis of metaphor with the analysis of a variety of other linguistic and conceptual phenomena. This framework—referred to variously as the theory of “blending”, “conceptual blending”, and “conceptual integration”—shares many aspects of CMT. For instance, both treat metaphor as a conceptual rather than a purely linguistic phenomenon; both involve systematic projection of language, imagery and inferential structure between conceptual domains; both propose constraints on this projection; and so forth.

Another theory, PT is a mode of graded categorization in cognitive science, where some members of a category are more central than others. According to Geeraerts (1989:587), PT was originated in the mid-1970s with Eleanor Rosch’s research into the internal structure of categories and the study of focal colors done by Anthropologists Brent Berlin and Paul Kay (1969). Geeraerts (1989) claims that the theory has caught the attention of linguists because the insights can be used to develop a model for dealing with such semantic phenomena as the fuzzy boundaries of lexical categories, the existence of typicality scales for the members of a category, the flexible and dynamic nature of word meanings, the importance of metaphor and metonymy as the basis of that flexibility. One of the most important findings is “family resemblance”, which is an internal structure of the category. It is this internal structure that made categorization in nature a cognitive activity.    英语混成新词建构新解多元理论视域(4):http://www.751com.cn/yingyu/lunwen_4512.html