Nitromagnesite
镁硝石
🗣️ 情景例句
It's too soon to know for certain.
现在还太早， 不知道确切情况 。
I visited her last Wednesday.
我上个星期三拜访她。
It was from the study of these that so much was learnt about the interior of the earth.
正是从这两种波的研究中，我们可以了解到地球内部的许多情况。