Thanks for enlightening me, tdol. I whizzed into usingenglish.com via google, and was not aware that it is an
ESL-focused site. One of the hazards of websurfing these days.
The simple explanations without elaboration make more sense in that context. We must simply trust that the poster of the idiom's explanation truly knows what they're talking about.
However, as a student of other languages such as Mandarin Chinese, I find myself most satisfied when I understand what's behind meanings, as it helps me avoid inappropriate uses.
A professor by the name of DeForest wrote a fabulous series of books starting with 'Beginning Chinese'. In each chapter, he put extensive and clear endnote references that expanded on grammar and meaning. That way, you could increase the depth of the lesson if you wanted.
I love that approach! It has been adding immeasurably to my understanding of the hows and whys of Mandarin Chinese. It is like having the teacher there tutoring you, so you can ask the 'why?' questions. Many texts are more like a lecturer up at the front of a big hall who does not answer those questions at all.
I do understand that clickable expansion on the meanings may not be practical for this site--but it still would enrich it, as you surely have advanced
ESL students as well as beginners, and inquiring minds want to know. That's the road to fluency.