【Abstract】Metaphor is another way to express things. In their book Metaphors We Live By， Johnson hold that metaphor is pervasive in our everyday life， not just in language but in thought and action. It could be claimed that EST， as a variety of English， is also metaphorical in nature. The metaphor of English in science and technology is to a large extent the nominal metaphor， by means of what we are familiar with， what we know to learn what is abstract and unknown.

【Key words】Lexical Metaphor； Grammatical Metaphor； EST

【作者簡介】朱曉紅（1993.03.22- ），吉林四平人，東北電力大學(xué)。

1. Introduction

Metaphor is a common linguistic phenomenon. The traditional view of metaphor regards metaphor as a figure of speech， which plays a role in the modification of language. Even technology text high technology contents， also borrows the language of daily life and other fields of vocabulary， this is a kind of metaphor， its essence is borrowed the concept of daily life and other disciplines in the means of the new science and technology concept.

1.1 Definition of Metaphor

Aristotle states quite clearly about the characteristics of the metaphor： metaphor is the transference of meaning. He also declares that metaphor is the process of making implicit comparison based in analogy principle. Both of them regard that metaphor as a kind of rhetorical phenomenon in which one word is used to substitute for another.

1.2 Research on Metaphor

Generally， the scientific research on logical thinking， conceptual thinking， mankind is the form of thinking， which reflects the thinking of scientific language is non context， does not have the cultural character， national character material form. Under the guidance of this theory， many translation theorists believe that the language of science and technology has only informative and information.

2. The Use of Lexical Metaphor in EST

2.1 Lexical Metaphor

EST refers to English of science and technology discourse. Modern metaphor theory holds that metaphor is understanding the objective world， it uses people familiar analogy to the unfamiliar， familiar functions， features， shapes， properties， process.

2.2 The Function of Lexical Metaphor

Interpretive function： Metaphor is ubiquitous in the scientific field， and the purpose of using metaphor is mainly to explain. The worlds personal computers are used in the office software， it has a lot of features and the same as the real office， which is a good explanation of the function， my documents， note， write. Popular function： To bring profound things into the peoples homes. Like our most commonly used computer mouse called trackballtoll.

3. The Use of Grammatical Metaphor in EST

3.1 The Form of Grammatical Metaphor

Grammatical metaphor is mainly the variation of grammatical structure， including the variation of certain word. The nominalizaiton mainly refers to that when people express concrete meaning， they choose the metaphor instead of the grammatical structure which is close to reality. Verb nominalization can be the process of the original verb， and it convert into noun. For examples： You can rectify this fault if you insert a wedge. Conversion：Rectification of this fault is achieved by insertion of a wedge. 如果插入一個楔子，你就可以糾正這一錯誤。

3.2 The Function of Grammatical Metaphor

Grammatical metaphor has the function of conciseness， and the process is the downward shift of grammatical order. The objective function can not be ignored， and the process embodied by the verb is reflected by the noun and becomes another process. The factors such as mood， modality， time， place and so on， which are related to the verb， are often omitted. The concept of transmission is changed from dynamic to static， which is universal and permanent in petroleum geology.

4. Conclusion

The study of metaphor of EST is still a new and tentative area and the complexity makes it a rather challenging job. Based on the research achievements by previous scholars and experts， this thesis tries to do a complete analysis of the phenomenon of metaphor in EST with the aim of attracting more people to be interested in the research of this area. The composition and function of grammatical metaphor reflects the improvement of peoples cognitive level and the evolution of human language. Grammatical metaphor increases lexical semantic value， which increases the complexity of scientific discourse.

References：

[1]Aristotle.“De Poetlca.”Ross W.D，The works of Aristotle Vol.[M].Oxford，Clarendon Press，1966.