Retrosinus
[医] 后窦(颞骨乳突)
🗣️ 情景例句
You don't need to do that, Grandpa.
你不用这样，爷爷。
I'll work for the next 5 days.
我要工作5天（从明天算起）
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。