双语的英文是“Bilingual”。根据英国著名的朗曼出版社出版的《朗曼应用语言学词典》所给的定义是:
A person who knows and uses two languages.
In everyday use the word bilingual usually means a person who speaks, reads, or understands two languages equally well (a balanced bilingual), but a bilingual person usually has a better knowledge of one language than of the other.
For example, he / she may:
a) Be able to read and write in only one language
b) Use each language in different types of situation, eg. one language at home and the other at work.
c) Use each language for different communicative purposes, eg. one language for talking about school life and the other for talking about personal feeling.
一个能运用两种语言的人。在他的日常生活中能将一门外语和本锋弊族语基本等同地运用于听、说、读、写,当然他的母语语言知识和能力通常是大于第二语言的。举例渗李来说:
他/她可能:
A) 使用一种语言来读和写;而用另银喊族一种语言来听,说。
B) 在不同的场合下使用不同的语言,如在家使用一种语言,在工作单位使用另一种语言。
C) 在不同的交际需要下使用不同的语言,如在谈论学校生活时使用一种语言,而用另一种语言谈论个人情感。