Substr
n. [数]子串函数；[数]字符截取函数；[数]取字符串的子串
🗣️ 情景例句
I have just begun to learn and my serve isn't very good.
我刚刚开始学习，发球不太好。
It's been a long time.
好久不见了。
Father Christmas is very kind-hearted.
圣诞老人心肠很好。