392. A language is a signaling system which operates with symbolic vocal sounds (语声), and which is used by a group of people for the purpose of communication.

译文

语言就是通过象征性语声起作用，并为了沟通的目的而被一群人使用的信号系统。

点睛

两个which引导的都是system的定语从句。operate with意为“借助……运转”。
for the purpose of意为“出于……的目的”。如：
This book is for the purpose of studying the very subject. 该书正是为研究此学科而写成的。

考点归纳

有关purpose的常见短语有：
on purpose意为“并非偶然地，故意地”。如：
They seemed to do those things on purpose. 他们似乎是有意做那些事的。
serve one's/the purpose意为“适合需要；令人满意”。如：
The plan will serve your purpose. 该计划会令你满意。
to little/no/some purpose意为“几乎没有／毫无／有一定成效”。如：
Money has been invested in the scheme to little purpose. 资金已投入到该方案之中，却几乎毫无成效。