I wonder how hard TagalogFilipino is to learn from a grammatical perspective. I mean, if you think about it, our monosyllabic particles alone are very diverse in functions ("ba", "pa", "nga", "sa", "na").
Like these particles alone can change the entire meaning of a sentence:
"Meron pa?" (surprised)
"Meron na?" (not surprised)
"Meron nga?" (don't lie to me)
"Meron ba?" (legitimately inquiring)
"Meron sa?" (finding)
A conversation:
"Meron bang kalabasa sa palengke?"
"Meron na."
"Kailan pa?"
"Kahapon pa."
"Magkano ba?"
"PHP30.00 na."
"Ang mahal na, ah."
"Oo nga."
EDIT: Changed "Tagalog" to "Filipino" because it's tantamount to saying langue d'oil is French, Castillian is Spanish, or Old English is Modern English.
I once downloaded and tried to read a reference grammar for Filipino (Tagalog, as it's indicated in the document). It was an interesting experience trying to make sense of that document with zero linguistics knowledge and only guessing using what I "innately know" of the language.
As far as "one particle changing the meaning of the entire sentence" I think a close analog would be the Japanese か/かな/ね used at the end of a sentence.
What's interesting is that I'm actually currently learning Japanese (actually, I have just started - currently finishing Wanikani G1 and JLPT N5) and, while resting from a kanji test, I decided to look at our language from a language learner's perspective. And I found it pretty hard HAHAHAHA. Like hell, how would I know if the "pa" in "hindi pa" means "yet" and not "more" (as in "isa pa") or "still" (as in "papunta pa lang").
Yep, Filipino is hard to analyze grammatically from a non-native speaker's perspective.
I actually have gone into that rabbit hole through an exchange student who who really wanted to learn our language. She asked a lot of questions about (basic) Filipino grammar, and we've probably spent more than an hour (in a 1.5 hour class "slot") arguing amongst ourselves about a fairly common grammatical construct. If I am recalling it correctly, it's something to do with what exactly the word ‘ay’ stands for, like in the sentence “Si nanay ay nagluluto” (which can be converted to “Nagluluto si nanay,” which started the entire argument).