Learn Hardcore Filipino: Ang bibilhin kong tiket ay para sa tren.

ang marks a specific, topicalized noun phrase. It often translates as “the,” but its main job is grammatical: it flags the topic of the clause.
Here, ang marks the whole phrase bibilhin kong tiket (“the ticket that I will buy”) as the topic.
Conversationally, people often use yung instead of ang. Plural is ang mga (e.g., ang mga tiket).

Why is it bibilhin and not bibili?

Root: bili “to buy.”
bibilhin is patient/object-focus (OF) future: the thing being bought is the ang-marked topic (here: the ticket).
bibili is actor-focus (AF) future: it highlights the buyer, and the thing bought is usually non-specific.
Compare:
- AF (non-specific): Bibili ako ng tiket. “I will buy a ticket.”
- OF (specific): Bibilhin ko ang tiket. “I will buy the ticket.”
In the sentence given, the ticket is specific and topical, so bibilhin fits.

What exactly is kong?

kong = ko
- linker -ng.
  - ko is the genitive pronoun (“I/my”) used to mark the actor in object-focus clauses: bibilhin ko = “I will buy.”
  - The linker -ng connects the modifier phrase (bibilhin ko) to the noun tiket to form a relative clause: “ticket that I will buy.”
Head-first alternative: ang tiket na bibilhin ko.

Is this a relative clause? Where is the word “that”?

Yes. bibilhin kong modifies tiket and means “that I will buy.”
Filipino doesn’t use a separate relative pronoun like “that.” It uses the linker -ng/na to attach the clause to the noun.
Equivalent paraphrase: Ang tiket na bibilhin ko ay para sa tren.

What does ay do? Can I omit it?

ay marks a topic–comment inversion and is common in formal or written style.
You can convey the same idea without ay by using the default predicate–topic order: Para sa tren ang bibilhin kong tiket.
Meaning stays the same; using ay just sounds more formal.

Why is it para sa tren and not para kay?

Use para sa with common nouns, things, and places: para sa tren, para sa opisina.
Use para kay with a singular personal name or title: para kay Maria, para kay Dok.
For plural names: para kina Maria at Juan.
With pronouns: para sa akin/iyo/kanya/atin/inyo/kanila.

Could I say “train ticket” instead, like tiket ng tren or tiket sa tren?

All are used, with slight nuances:
- tiket para sa tren — emphasizes intended purpose (“for the train”).
- tiket sa tren — common in speech; roughly “ticket for the train.”
- tiket ng tren — can read as a compound “train ticket” (classification), but context is needed because it can also mean “the train’s ticket.”

How do I pronounce bibilhin? Is bibilihin wrong?

Correct spelling: bibilhin (no extra “i” before the “h”).
Stress is on the final syllable: bi-bil-HIN.
Voice/aspect overview:
- Object-focus (patient focus): past binili, imperfective binibili, future bibilhin.
- Actor-focus: past bumili, imperfective bumibili, future bibili.

Can I rephrase the whole sentence more simply?

Bibili ako ng tiket para sa tren. (AF; non-specific ticket)
Bibilhin ko ang tiket para sa tren. (OF; specific ticket)
Para sa tren ang bibilhin kong tiket. (Predicate first; same meaning as the original)
Choose AF vs OF based on what you want to highlight and whether the object is specific.

Why is it kong and not ko na? How do I choose -ng vs na as a linker?

The linker attaches to the last word of the modifier phrase.
Use -ng after a vowel or after words ending in n (drop the final n: ilan → ilang).
Use na after other consonants.
Here, the modifier ends in ko (vowel), so we use -ng: kong.
Head-first version uses na because tiket ends in a consonant: ang tiket na bibilhin ko.

Is ko here possessive (“my ticket”) or the subject (“I will buy”)?

Here ko is the actor in an object-focus clause: bibilhin ko = “I will buy.”
Possessive ko attaches to a noun: tiket ko = “my ticket.”
bibilhin kong tiket means “ticket that I will buy,” not “my ticket.” The -ng shows bibilhin ko is modifying tiket.

Is tren the usual word? Can I say train?

Standard Filipino uses tren. In everyday speech, especially Taglish, you’ll also hear train, but tren is the native/standard form.