Naroon sa aparador ang pantalon ni Ana pagkatapos plantsahin.

Naroon means there or over there. In this sentence, it tells you where the pants are.

It is very close in meaning to nandoon. The main difference is style:

• naroon = a bit more formal or literary
• nandoon = very common in everyday speech

So Naroon sa aparador... and Nandoon sa aparador... would usually mean the same thing.

Filipino often puts the predicate first. In this sentence, the location comes first:

• Naroon sa aparador = is there in the closet/cabinet
• ang pantalon ni Ana = Ana’s pants

So the structure is closer to:

• There in the closet is Ana’s pants

In more natural English, we usually reorder it as:

• Ana’s pants are in the closet

But the Filipino word order is normal.

Sa is a very common marker for location, direction, or place. Here it means in/on/at, depending on context.

Aparador usually means a closet, wardrobe, or cabinet. The exact English word depends on the situation.

So sa aparador means in the closet/cabinet/wardrobe.

Ang marks the topic of the sentence. In many simple sentences, this is the noun phrase most similar to the English subject.

Here:

• ang pantalon ni Ana = Ana’s pants

Because Filipino often starts with the predicate, ang helps show which noun phrase is the main thing being talked about.

Ni Ana is the normal possessive form here, meaning Ana’s.

So:

• ang pantalon ni Ana = Ana’s pants

Use ni for possession with a personal name after a common noun like pantalon.

Kay Ana usually has other functions, such as to Ana, for Ana, at Ana’s place, or in some sentences belongs to Ana, but it is not the standard form in this specific noun phrase.

Here pantalon refers to the clothing item pants/trousers. Even though English uses a plural form (pants), Filipino treats pantalon as a normal singular noun.

So:

• ang pantalon ni Ana = Ana’s pants / Ana’s pair of pants

That is completely normal.

It means after ironing or after being ironed.

In this sentence, the understood object is the pants. So the idea is:

• after the pants were ironed
• or after ironing the pants

Filipino often leaves understood information unstated if it is already clear from context.

Plantsahin is the form used when the action is directed at an object: to iron something.

So:

• plantsahin = iron it / iron something
• magplantsa = do ironing / iron more generally

Because the sentence is about the pants as the thing being ironed, plantsahin fits well.

Very roughly:

• pagkatapos plantsahin = after ironing it / after it was ironed
• pagkatapos magplantsa = after doing the ironing

No. It does not say who ironed the pants.

The sentence only tells you that the pants are in the closet after the ironing happened. The doer of the action is left unstated.

That is very common in Filipino when the doer is unknown, unimportant, or already understood from context.

It is understandable and grammatical, but it sounds a little more formal because of naroon.

In everyday speech, many speakers would more likely say something like:

• Nandoon sa aparador ang pantalon ni Ana pagkatapos plantsahin.
• Nasa aparador ang pantalon ni Ana pagkatapos plantsahin.

So the original sentence is fine, but it has a slightly more formal or written tone.