Five years later, David Sarnoff helped create NBC.
VOA : special.2010.01.31
David Sarnoff was the man responsible for NBC.
David Sarnoff developed the theory of broadcasting.
英汉双解词典包含3185865条英汉词条，基本涵盖了全部常用单词的翻译及用法，是英语学习的有利工具。