试题题干
Translate the following sentence into Chinese.
Radio, telephone, and telegraph are means by which man has extended the range of his senses of hearing and speech.
参考答案
试题解析
考点：Radio收音机；telegraph电报；extend扩大； the range of······的范围。
句子结构： 句子主干为Radio, telephone, and telegraph are means，by which引导定语从句。