Unduloid
波状体
🗣️ 情景例句
What did I do with the rings?
我把戒指放哪儿了？
What will the weather be like tomorrow?
明天天气怎么样？
Once we get down to the oil, it usually flows to the surface because great pressure,
一旦到达油层，石油就会由于地下巨大的压力流到地面上来，