第二十三天

[nnozomi]

在 to show an action in progress (be doing something)
https://resources.allsetlearning.com/chinese/grammar/Expressing_actions_in_progress_with_%22zai%22

Since we've been discussing 在 in its other forms anyway! Constructive confusion.

Guardian:
爆米花呀。我还以为你们在研究长生晷呢。(It's popcorn! I thought you guys were researching the Longevity Dial.)
你到底有没有在听我说话？(Are you listening to me or not?)
但愿你知道你自己在做什么。(I hope you [want you to] know what it is you're doing.) Edited to correct my error, thank you presumenothing!

My practice:
在公园他们在打棒球。
他在喝今天第三杯咖啡。
如果你不在学习，帮我一个忙。

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