语言是人类表达思想感情的工具。通过嘴说,耳听构成了一种最简单和直接的通讯手段。大约一个世纪之前,电话的发明开辟了人类通讯的第一个新纪元。使远隔重洋的亲友,不受时间和空间的限制,可用电话直接通话,大大减轻了传递信息的劳动强度。七十年代计算机网络的建立开辟了人类通讯的第二个新纪 Language is a tool of human expression of thoughts and feelings. Through the mouth, ears make up one of the simplest and direct means of communication. About a century ago, the invention of the telephone opened the first new era of human communication. So distant relatives and friends across the ocean, without the restrictions of time and space, the phone can be used directly to talk, greatly reducing the labor intensity of the transmission of information. The establishment of a computer network in the 1970s opened the second epoch of human communication