Thank you everyone, really helpful.

I agree that 'can you work on this' sounds the most likely.

Maybe the teacher said, "Maco, would you talk to us?" (Perhaps you should ask the teacher.)

Hi, sorry about the late reply. "Can you work on this" is more broad, it could mean "could you start doing this?" or even "could you finish doing this?" (You had started it before, but have yet to finish.)

Thank you Chris. "Work on" is usually used when we start doing something - Let't work on the task. or still doing something - Hey, we are still working on. (a waiter in a restaurant tried to take away plates still some of food) In this context, is "Can you work on this" similar to "Can you start doing this"?