In particular the spag. I have never heard of a subordinating conjunction before. It has literally not been a thing that has touched my life. When I googled it, I recognised the thing in the description but I have never had to know the name. I have straight As all the way through secondary education and a good career and this is something I have never needed.
And they are making 10yos memorise this? And adverbials (also had to google). Ye Gods! Why?