Underset
n. 下层流, 下层矿脉
✅ 同义词
🗣️ 情景例句
I had lots of fun tonight.
今晚我玩得很开心。
Like tree, like fruit.
有其因必有其果。
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。