Cdh
abbr. constant differential height 常微分顶点
🗣️ 情景例句
Don't be lazy, the older you get, the harder it will be to learn.
别偷懒，年纪越大，学起来就越难。
He thanked them on your behalf.
他替你同他们致谢。
I know-it's you!
我知道－是你。