Serrasoid
锯齿波(调制)
🗣️ 情景例句
Six words.
六个字。
Are you required to fill a quota of work each month?
你被要求每月都要达成工作的目标吗？
This is because they had no natural enemies until the arrival of humans and therefore did not need to develop flying wings.
这是因为人类到达这里之前，这些鸟没有天敌，因此，它们不需要发育飞行的翅膀。