Radiospectrum
射频频谱
🗣️ 情景例句
He never drinks except on special occasions.
除非在特别场合，他从不喝酒。
They jumped at the unexpected noise.
他们因突如其来的声音吓得跳了起来。
I turned to look at the children, but there weren't any in sight: they had all run away! The man laughed when he realized what had happened.
我转过头去看那些孩子，但一个也不见，全都跑了！当那个人明白了发生的事情时，笑了起来。