Invulnerableness
n. invulnerable的变形
🗣️ 情景例句
Bye, Mom.
再见， 妈妈。
To jump
跃，跃起
and we have only to turn to that extraordinary discovery of echo-location in bats to see a case in which the voice plays a strictly utilitarian role.
我们只要看一看蝙蝠回声定位这一极不寻常的发现，就可以探究一下声音在什么情况下有绝对的实用价值。