Why is it ” I’m at work” but ” I’m in class”? Why does ” I’m in work” or “I’m at class” sound wrong grammatically?

Question

Why is it ” I’m at work” but ” I’m in class”? Why does ” I’m in work” or “I’m at class” sound wrong grammatically?

In: Other

Answer 1

I’m at work.

I’m in a meeting.

I’m at school.

I’m in class.

Work and school are locations you are *at.* Meetings and classes are activities you are *in* at those locations.