仅在KDKA电台首次广播的四年后，美国就有600家无线电台开播，其他国家也开播了一些广播电台。

Only four years after the first KDKA broadcast, there were six hundred radio stations in the United States. Radio stations also began to broadcast in other countries.

youdao

仅在KDKA电台首次广播的四年后，美国就有600家无线电台开播，其他国家也开播了一些广播电台。

Only four years after the first KDKA broadcast, there were six hundred radio stations in the United States. Radio stations also began to broadcast in other countries.

youdao