Replacement problem
[计] 置换问题
🧩 词语组成解析
🗣️ 情景例句
And I do feel bad about your mother
而且我觉得很过意不去让你母亲
Why are all those toys broken?
那些玩具为什么统统坏了？
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。