Diatreme
火山道
🗣️ 情景例句
Mom,
妈，
Does the back door have a lock on it?
后门上有锁吗？
Our knowledge of the oceans a hundred years ago was confined to the two-dimensional shape of the sea surface and the hazards of navigation presented by the irregularities in depth of the shallow water close to the land.
100年前，我们只知道海洋是二维平面形的，以及靠近陆地浅水区的深浅不一能给航行带来危险。