Serrasoid
锯齿波(调制)
🗣️ 情景例句
We've got a forty-minute drive into the city.
我们还要开四十分钟的车到城里去。
He likes playing the drum.
他喜欢打鼓。
Mr. Smith knew Jack didn't look at the others because he was nervous.
史密斯先生知道杰克不敢看别人是因为紧张。