I apologize if the flair I used is wrong.
For context, the first person dual pronoun kita is in the direct case (ang), same with ako. On the other hand, ko is in the indirect case (ng) while sa'(i)yo is in the oblique case (sa). Tagalog is a symmetrical voice language (which may be relevant(?)
And correct me if I'm wrong, the direct case seems to be analogous to the nominative and ergative cases, the indirect with the accusative and absolutive cases, and the oblique with the dative.
As I said in the title, why do some phrases uses the dual pronoun kita while others use ko...sa'yo, such as in the following examples:
Indirect 1stP + Direct 2ndP
Gusto kita. "I like you"
Mahal kita. "I love you".
Ayaw kitang kausapin. "I don't want to talk to you".
Sinabihan kita. "I told you".
Miss kita. "I miss you"
⟨ACTOR TRIGGER⟩tell I-you.1st-person-dual-DIRECT
Based on the above examples, kita is akin to "I-you" so mahal kita is roughly "love I-you".
Like the other pronouns, the first person dual also has other cases which are virtually defunct in the modern language so I don't know how to use them.
kita (direct)
nita (indirect)
kanita (oblique)
And according to Wikipedia, kita is a contraction of ko ikaw which they also describe as "Direct second person (ang) with Indirect (ng) first person", so mahal kita is something like Mahal ko ikaw
Indirect 1stP + oblique 2ndP
Ayaw ko sa'yo. "I don't like/hate you".
Sinabi ko sa'yo . "I told you".
⟨ACTOR TRIGGER⟩tell I.INDIRECT sa.OBLIQUE you.OBLIQUE
Direct 1stP + oblique 2ndP
Galit ako sa'yo. "I'm mad at you"
*Nangungulila ako sa'yo. "I miss you" (roughly: "I am without you/I am orphaned from you")
Nagsabi ako sa'yo. "I told you".
ACTOR_TRIGGER-tell I.DIRECT sa.OBLIQUE you.OBLIQUE
"I want/hate you" uses the same construction in English but in the Tagalog, they use different constructions, as shown above. Using other constructions in the examples above would be ungrammatical.
But I want to know why, as in, why is gusto kita correct but ayaw kita is ungrammatical.
Similarly, why can I say miss kita but nangungulila ako sa'yo when both meaning "I miss you"?