1. Radio and television have made it possible for advertisers to capture the attention of millions of people in this way.
    电台、电视使做广告的人可以用这种手段吸引成百万人的注意力。

2. I have a stereo radio.
    我有一个立体声录音机.

3. In the late 1940s, engineer Percy L. Spencer of the Raytheon Company was experimenting with high-frequency (高频率) radio waves.
    20世纪40年代后期，雷神公司的工程师珀西·L·斯潘塞正在从事高频无线电波实验。

4. It's cheaper to build radio towers than to string lines across mountain ridges,
    建造无线电发射塔要比翻山越岭架设线路更便宜。

5. Fortunately, a pilot saw the signal and sent a message by radio to the nearest town.
    幸运得很，一位飞行员看到这个信号，用无线电给最近的城镇发了报。