From the mailbox:
I am reading your explanation on caer and caerse and am interested to know if you have addressed morir and morirse. Not being a native speaker, those two verbs are very confusing for me and my students.The quick answer is that this is one of those cases where there isn't much difference — both verbs mean "to die." As explained in our new lesson on morir and morirse, the reflexive morirse may be more informal and maybe even a bit more respectful. Morir may be the safer choice if you're not sure which to use — just make sure to conjugate morir correctly!
Comments
I have seen morirse used to mean die in the figurative sense for instance me muero de hambre The way userlazurus1907 explained on Spanishdict morirse is unexpected. I would say fallecer is more the dignified way to mention that fact that someone has died just like the term pass away in English.
RAE third definition of morir is:
Sentir muy intensamente algún deseo, afecto, pasión, etc. (Usado más como pronominal) Morir de frío, de hambre, de sed, de risa.
I suppose it’s a personal preference consideration. I’m not a native speaker so I’ll play safe and prefer the RAE definition.
More likely, in formal usage and euphemism, “fallecer” would be preferable.