第九天

[nnozomi]

在, being in a place
https://resources.allsetlearning.com/chinese/grammar/Expressing_existence_in_a_place_with_%22zai%22

在 can be an -ing type of word also, but this one is just about location.

Guardian:
你打的是我办公室的座机。我当然在学校了。(Shen Wei giving Zhao Yunlan backtalk: you just called my office phone. Obviously I'm at school.)
那他办公的地方到底在哪儿？（Zhao Yunlan: so where the hell does he work?)
你不知道赵云澜在梦里多有趣 (Ye Zun screwing with his brother: you don't know how interesting Zhao Yunlan is inside his dreams.)

My practice:
因为我在家里工作，所以我可以一边工作一边听音乐。
我手机在哪里？啊，在充电中。
她女儿在学校学习英语。