Their competition and collaboration were creating the broadcasting industry in the United States, beginning with the introduction of commercialradio programming in the early 1920s.
从20世纪20年代早期引入商业广播节目开始,这些竞争与合作就在开创美国的广播产业。
2
There were no commercialradio stations until 1920.
直到1920年才有了商业电台。
《柯林斯英汉双解大词典》
3
If people running commercialradio do not recognise that, we are in worse trouble than I thought.