True. I am not up-to-date. But, from what I have seen, there have been no improvements in descriptive grammar that make diagramming any better or more fun. Reed-Kellogg is amazingly complete that way. Within that system, "that" as a function word is diagrammed differently from coordinating or subordinating conjunctions, or "transitional adverbs", for that matter. But, regardless of what you choose to call "that", I keep returning to the start of this thread which asked about diagramming. Probably within other systems of diagramming this "that" can be treated much as a conjunction.
"Preposition" within Reed-Kellogg is a word that begins a prepositional phrase, not one that begins a subordinate clause, and that matters greatly within the diagram of a sentence.
The difference between the British terms and the traditional American terms is virtually always present within this forum. Perhaps that is what is going on.
But... the diagram?
Perhaps I will diagram this sentence as a short video on my Youtube channel. I should probably do that. Reed-Kellogg diagramming is awkward and a chore on a computer, but a joy on a blackboard
Thanks, 5jj. (Typo -- in the diagram the category for "able to do it" should be AdjP, not VP.)
Very nicely done. Thanks.
Today at some point I will diagram the sentence on Youtube. I will alert this forum when I have uploaded it.
A very great difference between your system and Reed-Kellogg is all of the labeling. In R-K there is none. Everything is shown by the lines and the position of the parts. No doubt that is one of the reasons for its former great popularity. If you are unfamiliar with it, you may find it interesting. The sentence is very quickly done, once the syntax has been figured out, which, I believe is actually quite tricky because of the passive voice and the objective complement.