Quasiconvexity
拟凸性
🗣️ 情景例句
After studying an hour, I finally got the hang of the lesson.
我学习了一个小时，终于理解了这一课的要点。
No matter what happens, don't look excited.
不管什么事情发生，你总不要显得激动。
There is a picture on the wall.
墙上有一张画。