语言(language)
语言是同一个文化中的人所使用来互相沟通的一套口说或书写符号系统。语言反映并影响文化中的思考方式，并会随着文化中语言的发展而改变。原本相关的语言会因为使用者的互相隔离而越来越不同。当言语集团互相接触时（例如经由贸易或征服），它们的语言会互相影响。大多数现存的语言与其他从古老的语言传承下来的语言构成一族（参阅historical linguistics）。最大范围的语言分类是语族，举例来说，所有的罗曼诸语言源起於拉丁语，属印欧诸语言族的义大利分支，是继承古老的母语原始印欧语而来。其他主要语族有，亚洲的汉藏诸语言、南岛诸语言、达罗毗荼诸语言、阿尔泰诸语言和南亚诸语言；非洲的尼日－刚果诸语言、亚非诸语言和尼罗－撒哈拉诸语言；美洲的犹他－阿兹特克诸语言、马雅诸语言、奥托－曼格诸语言和图皮诸语言。追溯语言间的关系是以比较语法和句法，尤其是以寻求不同语言间同源词（相似的字）的方法来进行。语言拥有可以被分析并有系统地呈现的复杂结构（参阅linguistics）。所有的语言都是从言语开始，许多并继续发展文字系统。所有的语言都可以用不同的句子结构来表达语气。虽使用不同的层次来表达语气，但似乎都能表现出一种有弹性的结构上的平等。主要的层次有词序、构词、句法结构和言语中的语调。不同的语言保持了本身对数量、人称、词性、时态、语气和其他与字根分离或连结在一起的项目的指示法。人类天生学习语言的能力随年龄增长而减弱，且在约十岁之後所学习的语言其表达能力通常不会比在之前所学的语言还要好。亦请参阅dialect。
English version：
language
System of conventional spoken or written symbols used by people in a shared culture to communicate with each other. A language both reflects and affects a culture's way of thinking, and changes in a culture influence the development of its language. Related languages become more differentiated when their speakers are isolated from each other. When speech communities come into contact (e.g., through trade or conquest), their languages influence each other. Most existing languages are grouped with other languages descended “genetically” from a common ancestral language (see historical linguistics). The broadest grouping of languages is the language family. For example, all the Romance languages are derived from Latin, which in turn belongs to the Italic branch of the Indo-European language family, descended from the ancient parent language, Proto-Indo-European. Other major families include, in Asia, Sino-Tibetan, Austronesian, Dravidian, Altaic, and Austroasiatic; in Africa, Niger-Congo, Afro-Asiatic, and Nilo-Saharan; and in the Americas, Uto-Aztecan, Mayan, Otomanguean, and Tupian. Relationships between languages are traced by comparing grammar and syntax and especially by looking for cognates (related words) in different languages. Language has a complex structure that can be analyzed and systematically presented (see linguistics). All languages begin as speech, and many go on to develop writing systems. All can employ different sentence structures to convey mood. They use their resources differently for this but seem to be equally flexible structurally. The principal resources are word order, word form, syntactic structure, and, in speech, intonation. Different languages keep indicators of number, person, gender, tense, mood, and other categories separate from the root word or attach them to it. The innate human capacity to learn language fades with age, and languages learned after about age 10 are usually not spoken as well as those learned earlier. See also dialect.
