Really need to work on details. Objects are frequently a single color, as if there's no light reflection at all. Not even an attempt to add a simple gradient to things to show a half-decent light reflection effect. This distracted from scenes like the people walking into the door, because all I saw was two gray rectangles on top of a brown rectangle. No depth, no color, no anything.
No arms on the bodies or legs, to skip out on drawing a walk animation.
Also, the chain on the door is not at all convincing. Are those chains glued to the door? Two handles with a chain and a lock would have been more convincing. Maybe a 'do not enter' sign too.
When that guy fell over, I thought it was someone offscreen holding a ball in their hand. Again, no details. I didn't find this funny, but perhaps that's because I notice the details more than anything.
On the plus side, I did notice that you drew the columns and lots of other things perfectly straight instead of jagged and freehand. So you have some attention to detail.