作者：马文星
　　【Abstract】Redundancy is a language phenomenon that appears in every level of language and it is internal to language. This paper attempts to explain the forms and functions of redundancy through different levels of language with several examples， thus the value of redundancy is pursuit to help learners to obtain a deeper and better understanding in language learning.
　　【Key words】redundancy； ambiguity； comprehension
　　【作者簡介】马文星，女，甘肃庆阳人，西安外国语大学英文学院，2017级在读研究生，研究方向：外国语言学及应用语言学。
　　1. Introduction
　　In linguistics， redundancy refers to information that is expressed more than once. Redundancy by definitions from various scholars are noted as： “information available for more than one source” （Smith， 1971：132）； or redundancy is a critical feature in our communication and language in particular. （Darian， 1979）. According to the definition， many people regard redundancy as a negative feature of language， but it does make a difference in a particular way to forming human language.
　　2. Forms of the redundancy
　　In previous we mentioned redundancy exists in all level of language， and the types of the redundancy are divided into grammatical redundancy and contextual redundancy because the two could incorporate all kinds of redundancy.
　　2.1 Grammatical redundancy
　　Grammatical redundancy refers to a internal system and the rule manipulating language in which two or more of its forms that serve the same function. （Wit & Gillette， 1999）. In many languages， there is a agreement adjective when the subjective noun is in the different gender and number. For instance， in Russian： красивое， красивая， красивые. In English，， some affixes are obviously redundant， such as “inflammable” indicates the same meaning with or without the original word “flammable”. From those two examples we can assume that the grammatical redundancy is obligatory， which means the element of redundancy cannot be randomly deleted.
　　2.2 Contextual redundancy
　　Contextual redundancy， the repetition of the information， is voluntary and optional to the communication. When we discuss the contextual redundancy， we study it from the semantic and pragmatic perspective of language. Actually， in this paper we only talk about three of them.
　　2.2.1 Identical or synonymous repetition
　　Identical or synonymous repetition appears when the information contains two or more identical or similar meaning. Many literature works use it as a rhetoric way of reinforcing the effect of the emotional feeling. For examples： I had a big， big toy bear. I am entirely and completely crazy about her.