Learn Hardcore Filipino: Bilhan mo si Maria ng isda sa palengke.

Bumili = actor-focus (AF): emphasizes the one who buys
- Bumili ka ng isda sa palengke. – You buy fish at the market. (Focus = you)
Bilhan = locative/benefactive-focus (-an form): emphasizes for whom or where the buying is done
- Bilhan mo si Maria ng isda sa palengke. – Buy Maria some fish at the market. (Focus = Maria, the beneficiary)

In this sentence, Maria (the person who benefits from the action) is the focus, so the benefactive form bilhan is used. If we used bumili, the sentence would naturally focus on you as the buyer instead.

What is the role of si in si Maria?

Si is a personal marker used before singular proper names (people, sometimes pets or personified entities) when they are in the focus/nominative role.

In this sentence:

si Maria = Maria is the focused argument (the beneficiary of the action)
The verb bilhan is a benefactive-focus verb, so its focus argument is the beneficiary, and that argument is marked with si (or ang for common nouns).

Compare:

Bilhan mo si Maria ng isda. – Focus on Maria (beneficiary)
Bilhin mo ang isda para kay Maria. – Focus on ang isda (the fish), and Maria is now in a prepositional phrase (para kay Maria), not marked by si.

So si tells you Maria is the main, focused participant in this clause.

Why is it si Maria and not kay Maria?

Si and kay both relate to people, but they mark different grammatical roles:

si Maria = Maria as the focus/nominative argument (here: beneficiary in a benefactive-focus sentence)
kay Maria = Maria as an oblique argument, often after a preposition like para (for), galing (from), tungkol (about), etc.

Compare:

Bilhan mo si Maria ng isda.
- Benefactive-focus verb (bilhan)
- Focus = si Maria (beneficiary)
Bumili ka ng isda para kay Maria.
- Actor-focus verb (bumili)
- Focus = ka (you)
- Maria is expressed in a prepositional phrase: para kay Maria (“for Maria”)

So si Maria here means Maria is the grammatical focus of the sentence, while kay Maria would make her just an indirect object inside a prepositional phrase.

What does ng do in ng isda?

In ng isda, ng is a case marker for a non-focused direct object (also sometimes called “patient” or “theme”).

In this sentence:

Focus = si Maria (beneficiary)
Non-focus object = isda (fish), marked by ng

So the structure is roughly:

Bilhan mo – buy for
si Maria – the one for whom (focus)
ng isda – what you buy (non-focus object)

If the fish were the focus instead, you would typically mark it with ang or yung:

Bilhin mo ang isda sa palengke. – Buy the fish at the market. (focus = fish)

Is ng in ng isda the same as nang?

They are pronounced the same (/naŋ/), but they are spelled differently and have different functions:

ng (no “a”)
- Case marker for non-focus arguments (like ng isda).
- Also a linker between modifiers and nouns (e.g., magandang bahay, from maganda + ng + bahay).
nang (with “a”)
- Used as a conjunction (“when,” “so that,” “in order to”).
- Used before adverbs or repeated words (e.g., tumakbo nang mabilis – ran quickly).

In Bilhan mo si Maria ng isda sa palengke, only the case-marker ng is used: ng isda = fish (as non-focused object).

Why is there no word for “some” before isda?

In Filipino, when you talk about an unspecified amount of a mass noun (like fish, rice, water), you usually just use the bare noun with its marker:

ng isda can naturally mean “(some) fish”
ng tubig = (some) water
ng bigas = (some) uncooked rice

If you really want to highlight quantity, you add a quantifier:

ng kaunting isda – a little fish / a bit of fish
ng maraming isda – a lot of fish
ng tatlong isda – three fish

So ng isda already carries the idea of “fish (unspecified amount)” without needing a separate word for “some.”

Is isda singular or plural here?

On its own, isda is number-neutral. It can be translated as “fish” in general, with the number understood from context.

To make it clearly plural, you normally add mga:

ng isda – fish (one or some/any; context decides)
ng mga isda – fishes / several fish (more clearly plural)

In everyday speech, ng isda in a sentence like this is usually understood as “some fish,” not strictly “one fish,” unless the context says otherwise.

What is the function of sa palengke?

Sa palengke is a locative phrase; it tells you where the buying happens.

sa – general marker for locations, directions, and some indirect objects
palengke – market

So sa palengke = “at the market” / “in the market”.

You’ll see sa used this way very often:

sa bahay – at home
sa opisina – at the office
sa tindahan – at the store

In this sentence, sa palengke is not the focus; it’s an additional location detail attached to the action of buying.

Can I move the parts around, like Bilhan mo ng isda si Maria sa palengke? Does the meaning change?

Filipino word order is relatively flexible, especially for arguments that are already marked by si/ng/sa. All of these are grammatical and keep the same basic meaning:

Bilhan mo si Maria ng isda sa palengke.
Bilhan mo ng isda si Maria sa palengke.
Bilhan mo si Maria sa palengke ng isda.

Nuances:

Speakers often like to place the focus element (here si Maria) near the verb or toward the end for emphasis.
Moving si Maria and ng isda around may slightly affect emphasis (who you are conceptually centering in the sentence), but the role of each phrase is still clear because of si and ng.

What you generally cannot do is remove the markers and rely only on word order (like in English), because Filipino depends heavily on case markers (si/ng/sa) to signal roles.

Why is the pronoun mo used instead of ka or ikaw?

Filipino has different pronoun forms depending on case/role:

ikaw / ka – nominative (used for focus in actor-focus sentences)
mo – genitive/ergative (used for the actor when the verb is not actor-focused)

In this sentence, the verb bilhan is not actor-focus; it’s benefactive-focus. That means:

The focus is si Maria, not “you”.
The actor (“you”) is non-focus and therefore marked with the genitive form mo.

Compare:

Bumili ka ng isda. – actor-focus; ka is focus.
Bilhan mo si Maria ng isda. – benefactive-focus; si Maria is focus; mo is the non-focus actor.

So mo is used here because “you” are the actor in a non-actor-focus sentence.

Is this sentence a command, like “Please buy Maria some fish,” or a statement?

With bilhan in this bare form plus mo, the most natural reading is an imperative/command:

Bilhan mo si Maria ng isda sa palengke.
≈ Buy Maria some fish at the market.

To express different aspects or tenses, Filipino usually changes the form of the verb:

Binilhan mo si Maria ng isda sa palengke. – You bought Maria some fish at the market. (completed)
Bibilhan mo si Maria ng isda sa palengke. – You will buy / are going to buy Maria some fish at the market. (contemplated/future)

To sound more polite or softer as a request, speakers might add polite markers:

Paki-bilhan mo si Maria ng isda sa palengke. – Please buy Maria some fish at the market.
Bilhan mo naman si Maria ng isda sa palengke. – (softened/imploring tone)

Could this sentence mean “Buy fish from Maria at the market”?

No, not with si Maria in this position and with this verb form.

In Bilhan mo si Maria ng isda sa palengke:

si Maria = beneficiary (the one you’re buying for)
ng isda = the thing bought (fish)
sa palengke = where you do the buying (the market)

To mean “Buy fish from Maria at the market,” Maria would be the source, not the beneficiary. You would normally mark that with kay after a different verb structure, for example:

Bumili ka ng isda kay Maria sa palengke. – Buy fish from Maria at the market.

So the original sentence is clearly “buy (some) fish for Maria”, not “buy (some) fish from Maria.”

Is there a simpler way to say this using an actor-focus verb?

Yes. You can switch to an actor-focus verb and use a prepositional phrase for “for Maria”:

Bumili ka ng isda para kay Maria sa palengke.

Comparison:

Bilhan mo si Maria ng isda sa palengke.
- Verb: bilhan (benefactive-focus)
- Focus: si Maria (beneficiary)
Bumili ka ng isda para kay Maria sa palengke.
- Verb: bumili (actor-focus)
- Focus: ka (you, the buyer)
- Maria is now in para kay Maria, a prepositional phrase.

Both are natural. Which one you use depends on whether you want to grammatically highlight the beneficiary (Maria) or the actor (you).