Question: Can I use "ay" for a NG clause?

If I'm not mistaken, "ay" is really used in NG clauses (the uncertainty is because the rules come natural to me so I'm not sure about the terms used). Here are some pointers though. I hope these help.1A) There is no "papakain", though there is "magpapakain" and "papakainin/pakakainin"1B) If you meant "You will have your child to eat," then:
- [Magpapakain] Ikaw ay magpapakain ng anak. = You are going to feed your child. ["ng" instead of "ang"]
- [Papa/pakakainin] Papa/pakakainin mo ang anak mo. = You are going to feed your child./You are getting your child to eat. [the "mo" at the end is needed to specify whose child it is, unlike the previous example]1C) But if you meant "You will have the child to eat," then:
- Ikaw ay magpapakain ng bata.
- Papa/pakakainin mo ang bata.2A) "Ikaw ay kinain ang gulay." needs one of these two adjustments to grammatically make sense but only the latter to actually make sense😆:
- Ikaw ay kinain ng gulay. = A vegetable ate you./You were eaten by a vegetable.
- Ikaw ay kumain ng gulay. = You ate (a) vegetable. [from IN to UM verb]2B) "Kinain mo ang gulay." can mean "You ate THE vegetable." but it can also mean "You ate vegetable." sometimes for some people. Another way you can say it is:
- Kumain ka ng gulay. = You ate (a) vegetable. [Though this can also be an imperative depending on tone and context]

@DenC Thank you for the answer.
I see, "ay" can not be used for the way I showed.Thank you too for correcting my sentence.As for (1), my example should have been:
"Ikaw ay papakain papakainin mo ang anak mo. "
Then this is NOT corret usage for ay.

@shin23 Yes, because there are other ways you can say things. For example, if you want to say:
1) [You have a good heart./Your heart is good.] Instead of "Ikaw ay mabuti ang kalooban," you can say:
- Ang kalooban mo ay mabuti.
- Ikaw ay may mabuting kalooban. ("may" = have)
- Mabuti ang kalooban mo. Here's a reference about the pronouns you can use with ang, ng, and sa. languagecrush.com/bo ok/3/207/chapter

@DenC Thank you for the alternative example and the link.

I don't understand what you mean by "Can I use "ay" for a NG clause?", but I will explain to you the structure of the sentence from the podcast."Ang NASA Airborne and Satellite Investigation of Asian Air Quality science mission ay paliliparin NANG apat na beses ang kanilang DC-8 aircraft. " (The “NG apat…” should be “NANG apat…” because “apat na beses (four times)” functions as an adverb.)That sentence from the podcast uses two “ang”s. Such a sentence may be made and would be acceptable if:
1. The verb is object-focus, but we want to give focus to both Actor and Object.
2. There is no Indirect Object.
3. Both Actor and Direct Object are common nouns or nouns that may be preceded by the article “ang”, e.g., ang NASA, ang aircraft.
4. The sentence is stated in the subject-predicate form, i.e., using “ay” between the subject and predicate. The Actor is treated as the Subject and the Direct Object is the subject of the predicate. Actor/Subject: Ang NASA … mission
Predicate: ay papaliparin ... aircraft
Direct Object: ang kanilang (DC-8) aircraft“Papaliparín ang kaniláng aircraft.” = Ang kaniláng aircraft ay pápaliparín. = Their aircraft will be made to fly.
“Ang NASA ay papaliparin ang kanilang aircraft. (NASA will fly their aircraft.)We don’t usually state sentences that way, and I suggest that you should not consider doing it yet at your level. It’s because such sentences can easily be misstated, and you might be misunderstood or sound ridiculous. The standard ways to state that sentence are:
Subject-focus:
Ang NASA ay MAGPÁPALIPÁD ng kanilang aircraft.
MAGPÁPALIPÁD ” ang NASA ng kanilang aircraft.
MAGPÁPALIPÁD ng kanilang aircraft ang NASA.Object-focus:
Ang kanilang aircraft ay PÁPALIPARÍN ng NASA.
PÁPALIPARÍN ng NASA ang kanilang aircraft.Lastly, please follow the advice given by "DenC" on how to correctly express your sentences. Also, there is no "papakain" verb.

@Juantutri Thank you for the detailed explaination about the sentence from the podcast.> “Ang NASA ay papaliparin ang kanilang aircraft. (NASA will fly their aircraft.)
It is possible to say this way under the 4 condition you mentioned.
and this structure is rare case as you said.> there is no "papakain" verb.
Oh, I still mistook. Sorry, I edited.