I think the confusion is that 'dancing' and 'leaving', etc can be verbs or nouns - depending on the context. Here they are verbs ('doing' words): I am leaving in the afternoon. I was dancing all night.
Here they are nouns (things) as gerunds: I hope her leaving won't be painful for me. The.best dancing can be found at Club Tropicana. ('80s child here).
I teach year 4. We're going to do some work on suffixes next week. I've been merrily making lists of words and suffixes for them to experiment with. My top set are going to need a challenge though. In searching I've got myself all tied up in knots and generally confused...
What, in simple it's Sunday evening and I've done enough planning already year 4 terms, is a gerund?
I've grasped that its formed from a verb plus -ing... but is there more to it than that? Googling is not helping as I'm getting stuff too techy for my poor scientist-turned-teacher brain.