Quadric
a. 二次的\\nn. 二次曲面
🗣️ 情景例句
He was my roommate in college.
他是我大学时的室友。
Delivery costs will have to be borne by the manufacturer, I'm afraid.
运费恐怕要由制造厂商来承担。
We'll take all that you can give us.
你们有多少就买多少。