Orcin
n. [化]苔黑素,苔黑酚
??? 情景例句
Nope.
不
Are you free tomorrow?
你明天有空嗎？
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.
我們只要看一看蝙蝠回聲定位這一極不尋常的發現，就可以探究一下聲音在什么情況下有絕對的實用價值。