Improper quadric
[计] 异常二次曲面
🧩 词语组成解析
a. 二次的\\nn. 二次曲面
🗣️ 情景例句
Yes. When you get on the transfer bus, just show the bus driver this ticket stub.
要。当你上了转乘的公共汽车时，就把这张票根给司机看。
After a while,we found a shady place under some poplar trees.
在一会儿以后，我们在一些白杨树下面发现了一块遮阴的地方。
I often go-swimming, sometimes in a lake near my home, and sometimes in the river.
我经常去游泳，有时在我家附近的湖里，有时在河里。