two-tone的用法和样例：
词汇搭配
- two-tone dyeing 双色调染色
- two tone telegraph system 双音电报制
- two tone telegraph detector 双音电报检测器...
- two tone transmission 双音频传输制...
- two tone modulation 双音调调制
- two tone working 双音工作制
- two tone channel 双音通路
- two-tone stripe 双色条纹
- two tone system 双音系统
- two-tone keying 双音频键控
- two tone detector 双音检测器
- two-tone modulation 双音频调制
- six channel two tone 六路双音
- two-tone paint 双色油漆
- two tone method 双音信号法
- two tone keying 双音键控
