【文章內(nèi)容簡(jiǎn)介】 understanding figures of speech 15 Context analysis 16 Linguistic context 17 Cultural context 18Chapter Four Development prospect of machine translation 20 Technologies 20 Applications 20Conclusion 22Bibliography 23vIntroductionMachine translation, or MT for short, is the process of using machine to translate a language into another one. It is an interdisciplinary field of linguistics, natural language processing, artificial intelligence and so on. The ultimate goal of machine translation is to achieve fully automatic translation of natural language.The notion of using digital puters to translate documents was first put forward by Warren Weaver in 1949. From then on, machine translation had embarked on a long and devious road. At the very beginning, people were excessively optimistic about machine translation. They predicted that imminent breakthroughs of fully automatic systems would e soon. However their enthusiasm was dampened as more and more plicate linguistic problems became more apparent. For example, first, not all the words in one language have equivalent words in another one。 Second, many words are polysemantic and sometimes a sentence may have at least two meanings in a language but puter is not able to decide the exact meaning in the source text. Third, the ways of how sentences are put together are not the same in different languages. These above mentioned challenges are only the tip of the iceberg. In addition, the disappointing translation results of early translation systems frustrated people’s efforts in machine translation research. Researchers began to question the possibility of full automation and good quality However, the spectacular advancements of puter technologies and putational linguistics bring machine translation to life again. These advancements include increased processing speed, enlarged puter memory and improved database technology etc. Besides, there is a strong connection between machine translation and the modern society. For example, when exporters market their products in a foreign country they definitely need documents in the language of that country. Governments and all kinds of organizations are in great need of faster and cheaper translations. Spurred by all these factors, the passion of researchers was ignited again. As a result, many useful MT systems came into being one after another and are widely used to aid humans in translating various materials about science, industry, journalism etc. And, most significantly, pared to human translation, the machine translation systems featuring low cost and rapid response are able to increase the volume of immediate translations manifold, addressing the social need of quick translation of materials in a foreign language. What’s more, the emergence of the Internet brings about an increasing demand of timely translation online, which is insurmountable to human translators. Generally speaking, machine translation is used in two ways. One is the need of accurate translation, especially the translation of materials like news, laws, advertisings, product specifications etc. Here machine provides humans with a draft translation to be refined, thus saving a lot of time which would otherwise be wasted in consulting dictionaries. The other is the need of quick translation results which may be grammatically imperfect and lexically awkward but convey the main idea of the source text.Despite the tremendous improvement of machine translation since its emergence, there is still a long way to go before achieving the final goal of fully automatic translation. Machine translation is still confronted with a lot of technological bottlenecks which haven’t been tackled yet. The application of machine translation is restricted for it can’t be used to translate literary works, laws etc. The translation of machine translation usually is unreadable and grammatically wrong. The processing unit of machine translation is within sentence, so it is not able to analyze the relations between neighboring sentences or paragraphs. Furthermore, machine translation lacks the ability to analyze the context. As is well known, context plays an important role during translation. The meanings of words or sentences depend heavily on context, so the deficiency to analyze it will easily lead to mistranslation. American inventor Ray Kurzweil once predicted that by 2029 the quality of machine translation would reach the level of human translation. This prediction has triggered heated controversy in the academic munity. Anyway, the current development trend of machine translation is favorable. It is believed that machine translation has promising prospects in the future. As long as linguists, puter experts, mathematicians etc work collectively, all the bottlenecks facing machine translation will be solved.This paper will try to give the readers a coherent picture of many aspects of machine translation, mainly its advantages and disadvantages.Chapter One The evolution of machine translation since its emergence Development of machine translation in foreign countriesMachine translation dates back to as early as 17th century. In the early of this century, Ren233。 Descartes put forward an innovative idea of a universal language in which equivalent meanings of different languages can be expressed in the same way. Then in 1940’s, British engineer Andrew Booth and American scientist Warren Weaver jointly proposed to use puters to translate natural languages for the first time. Strictly speaking, the concept of machine translation was officially put forward in Warren Weaver’sMemorandum on Translation in 1949, which stimulated the research of MT in US. Henceforth, MT embarked on a winding and long path of development, which can be divided into the following 4 periods. Pioneering period（19461964）In 1954, Georgetown University and IBM of US collectively succeeded in inventing the f