Fifteens
n. 十五( fifteen的复数形式 ); 十五的; 十五岁
🗣️ 情景例句
And, Mrs. Stewart, are you working?
嗯， Stewart太太， 你有工作吗？
During the two years since I took charge of the department.
在我负责这个部门的两年中。
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。