Building things is when you construct something. It could be when you construct a tower of coins, or when you build a skyscraper. It doesn’t have a set size or shape, it is just when you put two or more physical objects together to make something else.

Very recently, I built a Lego model of a WW1 battle scene. I was very engaged and happy while building. I built it with my dad and brother. This is an image I just took of it: