Japanese phrase
___中です。 ___ chū de su
Meaning
___ is in progress.
When to use it
Shows that an activity is happening now. It politely indicates that someone is occupied with that activity.
Example dialogue
今、少し話せますか？ ima suko shi hana se ma su ka
Can you talk now?
すみません、仕事中です。 su mi ma se n shi goto chū de su
Sorry, I am working right now.