Dacryocystis
[醫(yī)] 淚囊
??? 情景例句
Advice doesn't normally come cheap, but this piece is for free...
通常來說，忠告都是價值不菲的，但這個是免費贈送的。。。
Choose an author as you choose a friend.
選書如擇友。
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(fā)現(xiàn)，就可以探究一下聲音在什么情況下有絕對的實用價值。