Polyphosphazenes
[化] 含磷氮鏈聚合物
??? 情景例句
Let's meet more often.
讓我們常見面。
It's wrong to break the law.
犯法是不對的。
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。