Translation orinterpretation is generally viewed as one of the results in the learning of anadditional language other than the mother tongue, or as an application of the masteryof at least two languages. However, together with translation or interpretationcome two by-products which are seldom explored in literature. One is thattranslation and interpretation incur double-learning or even multilearning,thus reducing the efficiency of language learning to much less than 50%. Theother is that translation and interpretation cultivate interlanguages that areerrors very difficult to eliminate. By analysing the causes and sources of suchby-products, this article aims at proposing an understanding of whattranslation and interpretation have really achieved in the communicationbetween different language users and in their learning of additional languages.

Keywords:translation, interpretation, double-learning, interlanguage, efficiency.

翻译可看做是母语之外学习了另一门语言的结果，亦可看做是掌握至少双语后的一种应用。然而，翻译却产生了文献中少有涉及的两种副产品。一种是重复学习，甚至多重重复学习，致使语言学习效率远低于50%。另一种就是造就了綦难消除的语言错误，即被称作“介语” [1]的非此非彼的言语。通过分析这两种副产品的起因及来源，本文旨在揭示不同语言的使用者之间交流及语言学习过程中翻译的真实作用。

关键词：笔译，口译，重复学习，介语，效率。