例句與造句

1. Frequency modulation radio originated in the United States during the 1930s; the system was developed by the American electrical engineer Edwin Howard Armstrong.
2. He invented automatic telephone equipment, a " time compressor " to accelerate recorded speech, high-power radio amplification, a frequency modulation radio altimeter, and several antenna matching and feeding systems.
3. It's difficult to find frequency modulation radio in a sentence. 用frequency modulation radio造句挺難的