I was telling my six year old daughter that dogs were unpredictable asked me what "to predict" means. I told her it means "to guess what will happen" and realized I had used a noun clause "what will happen." I realized I could have said, "to guess the future," but she was not clear about what "future" meant.
I was watching "Dinosaur Train" with her when they define "hypothesis" as "an idea that you can test" and saw an adjective clause in there "that you can test." It tells us "what kind" of idea, and "what kind" is a question that adjectives answer.
So, based on these examples, I'd like to put forth that clause patterns are not necessarily to be considered so difficult, but a way we use to simplify difficult or conceptual vocabulary words.