“Ang lalaki may marumi kuwarto” is not a well-constructed Filipino sentence as it lacks coherence. It would be equivalent to saying, “The man there is dirty room” in English.
Let’s consider each word of that sentence:
There are 2 entities - “lalaki” (man) and “kuwarto” (room). Either of them could have been the subject of the sentence. However, by having “ang” before “lalaki”, it makes “lalaki” as the subject and “kuwarto” will become part of the predicate. (The rule: “Ang” introduces a common noun when used as the subject of a sentence).
“May” can mean “there is” or “to have”. In the absence of context, we would give it the “there is” meaning.
“may aso” = there is a dog
“may aso sa bahay” = there is a dog in the house
“may aso si John” = John has a dog.
“Marumi” is “dirty”, but it can only function as an adjective (a modifier/describer) of “kuwarto” if it will be linked to it. In English, an adjective before a noun automatically becomes its modifier. So, “white” in ”white house” is a modifier of “house”. In Filipino, an adjective does not automatically modify a noun after it unless we use the linker “NA” to connect them. If we are to say “puti bahay”, to us it would sound as awkward as “house white”. But if we are to add a “na” between them, “puti na bahay”, then we would understand that as “white house”. (Note: “Puti na bahay” would be more commonly expressed as “puting bahay”.) In fact, even if we now put the noun before the adjective, for as long as the “na” is between them, the meaning is the same - “puti na bahay”/”puting bahay” = “bahay na puti” = white house.
Given that in the sentence you gave it began with “ang lalaki”, that makes it the subject based on the rule stated above. For the sentence to make sense, the rest has got to be the predicate and the word “ay” is needed to link them. In other words, the sentence structure will follow the subject-predicate (active voice) form. The correct sentence then becomes:
“Ang lalaki AY may maruming kuwarto” = The man has a dirty room. (Context gives “may” the “to have” meaning)
The inverted (predicate-subject) order of that sentence would be:
“May maruming kuwarto ang lalaki” = The man has a dirty room (“Ay” disappears in the predicate-subject order, but meaning is the same)
Is that what you really wanted to say? Or is that how you wanted to say it? Maybe not and I guess that’s why FilipinoChatAdmin also changed your sentence.
Here’s why. Note that I mentioned 2 entities above - man and room - and also said that either of them can be the subject of the sentence.
1. The MAN has a dirty room.
2. The ROOM of the man/The man’s ROOM is dirty.
The Filipino sentence we have above translates to sentence #1. However, maybe it’s sentence #2 that you really meant to say, i.e., the preferred subject (and therefore, the focus) is the “room” instead of the “man”.
Using “kuwarto” (room) as the subject now, the subject-predicate form of the sentence becomes:
“Ang kuwarto ng lalaki AY marumi” = The room of the man/man’s room is dirty.
Putting that sentence in the inverted (predicate-subect) order, it becomes:
“Marumi ang kuwarto ng lalaki”
And that’s the sentence that FilipinoChatAdmin gave you. It places the focus on “kuwarto”, which I also believe should be the case and it follows the more common way now of expressing a Filipino sentence, which is in the predicate-subject form.
BTW, the correct spelling of the word is “buwisit” or “bwisit”. It’s a Filipino expression that means “what a nuisance!” and may have the same effect as saying “damn it!” in English. If you’d say it directly at someone though, it would mean “you’re a pest!” or “damn you!” and that might get you into trouble. 😀
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