Kaibigan ko ang kausap.

A natural word-by-word breakdown is:

• kaibigan = friend
• ko = my / of me
• ang = a marker that highlights the topic or definite noun phrase
• kausap = the person being talked to / spoken with, or more naturally, the one being spoken to / the person I’m talking with

So the sentence is an equational sentence: it identifies who the kausap is.

In Filipino, short pronouns like ko often come after the word they relate to.

So:

• kaibigan ko = my friend
• literally, something like friend my

This is normal Filipino word order. Similar examples:

• bahay ko = my house
• nanay ko = my mother
• kotse ko = my car

So kaibigan ko is simply the standard way to say my friend.

Ang marks the topic or the noun phrase being identified in the sentence.

In Kaibigan ko ang kausap, the structure is roughly:

• Kaibigan ko = the predicate or description
• ang kausap = the topic, the one being identified

So the sentence is like saying:

• The one being spoken to is my friend
• or The person I’m talking to is my friend

In Filipino, this kind of sentence often puts the description first and the ang-marked topic second.

Because Filipino often puts the predicate first.

English usually says:

• The one I’m talking to is my friend

Filipino commonly says:

• My friend [is] the one I’m talking to

That is exactly what is happening in:

• Kaibigan ko ang kausap

This is very normal in Filipino. The language does not always follow the same subject–verb–object expectations that English learners are used to.

Yes, from an English point of view, it feels like there should be an is, but Filipino often leaves that out in this kind of sentence.

So:

• Kaibigan ko ang kausap

  literally looks like:

• My friend the one being spoken to

But grammatically it means:

• The one being spoken to is my friend

Filipino often forms this kind of “X is Y” sentence without a verb like “is.”

Yes. That is also correct.

• Kaibigan ko ang kausap
• Ang kausap ay kaibigan ko

Both mean the same basic thing.

The difference is mainly in style and structure:

• Kaibigan ko ang kausap is a common predicate-first pattern.
• Ang kausap ay kaibigan ko is a more explicitly divided topic + comment structure because of ay.

The version with ay can sound a little more formal or more carefully structured, though it is very common and natural too.

Kausap means the person someone is talking with or to in a conversation.

It comes from the root usap, which is related to talking or conversation.

So kausap is not just any person nearby. It specifically means:

• conversation partner
• the person being talked to
• the one someone is speaking with

In this sentence, ang kausap means the one being spoken to / the person being talked with.

No.

Kausap is the person someone is talking with, not necessarily the one doing the speaking in the English sense of speaker.

Depending on context, it usually means:

• the person I’m talking to
• the person someone is conversing with

So Kaibigan ko ang kausap does not mean:

• My friend is speaking

It means:

• The person being talked to / spoken with is my friend

If you wanted to say My friend is talking, you would need a different structure, such as one using a verb.

Because kausap here is a common noun, not a person’s name.

In Filipino:

• si is used for personal names
• ang is used for common nouns or noun phrases

So:

• si Maria = Maria
• ang kausap = the person being talked to

If you replaced kausap with a person’s name, then si would be appropriate:

• Kaibigan ko si Maria = Maria is my friend / My friend is Maria, depending on context

But kausap is not a name, so ang is correct.

Not naturally.

Because kaibigan ko specifically means my friend, not just the friend.

Also, the ang-marked phrase is the topic being identified. So the sentence is most naturally understood as:

• The one being spoken to is my friend

If you wanted the friend in a more general sense, you would usually need a different expression.

Not in the traditional English-school grammar sense.

In many Filipino grammar explanations, it is more useful to think in terms of:

• topic: the phrase marked by ang
• predicate/comment: what is said about that topic

So in:

• Kaibigan ko ang kausap

you can think of it as:

• Topic: ang kausap
• Comment/Predicate: kaibigan ko

That is why many learners get confused if they try to force English subject rules directly onto Filipino.

Yes, that is a good literal-style translation.

Depending on context, natural English versions might be:

• The person I’m talking to is my friend
• The one being spoken to is my friend
• The person being talked to is my friend

The best English version depends on the situation, but your literal understanding is on the right track.

You would make the relevant noun phrase plural.

For example:

• Kaibigan ko ang mga kausap = The people I’m talking to are my friends
• Mga kaibigan ko ang kausap = The ones being spoken to are my friends / The people being talked to are my friends

A few things to notice:

• mga marks plurality
• kaibigan ko can become mga kaibigan ko = my friends
• ang mga kausap = the people being talked to / spoken with

So plural is handled by adding mga where needed.