Ons weet waaroor hulle praat.

Waaroor is a common Afrikaans prepositional adverb. It is made from:

• waar = what / where in certain compound forms
• oor = about / over

So waaroor means about what or what ... about, depending on the English wording.

In this sentence, Ons weet waaroor hulle praat, it means what they are talking about / what they’re talking about.

Afrikaans very often combines waar + preposition into one word:

• waarop = on what
• waarin = in what
• waarmee = with what
• waarvoor = for what
• waaroor = about what

Because waaroor hulle praat is a subordinate clause.

In Afrikaans, when a clause is introduced by a word like dat, omdat, as, or an interrogative/relative word like waaroor, the conjugated verb usually goes to the end of that clause.

So:

• Main clause: Ons weet
• Subordinate clause: waaroor hulle praat

That is why the order is:

• waaroor = about what
• hulle = they
• praat = talk

and not waaroor hulle praat with the verb earlier.

Afrikaans verbs are much simpler than English verbs in this way. They usually do not change form for different persons.

So you get:

• ek praat
• jy praat
• hy/sy praat
• ons praat
• hulle praat

The same basic form is used for almost everyone.

Likewise with weet:

• ek weet
• ons weet
• hulle weet

So hulle praat is completely normal: no extra ending is needed.

Ons means we.

It is the subject of the main clause:

• Ons weet = We know

So the sentence has two parts:

1. Ons weet = We know
2. waaroor hulle praat = what they are talking about

Together: We know what they are talking about.

Sometimes learners expect oor wat because it looks closer to English about what. But in standard Afrikaans, waaroor is the normal and natural form here.

So:

• Ons weet waaroor hulle praat. = natural
• Ons weet oor wat hulle praat. = much less idiomatic, and often treated as non-standard or awkward in careful Afrikaans

A good rule for learners is:

• when English has preposition + what/which, Afrikaans often prefers waar + preposition in one word.

Yes, but that would be a direct question, not the same structure as your sentence.

Compare:

• Waaroor praat hulle? = What are they talking about?
• Ons weet waaroor hulle praat. = We know what they are talking about.

In the direct question, the verb comes earlier:

• Waaroor praat hulle?

In the embedded/subordinate clause, the verb moves to the end:

• waaroor hulle praat

This is a very important Afrikaans pattern.

Yes. Even though waar often means where, in combinations like waaroor, waarmee, waarvan, etc., it does not refer to place.

Here waaroor means about what — the topic of the conversation.

So in this sentence, the meaning is about subject matter, not location.

A simple learner-friendly pronunciation guide is something like:

VAA-r-ohr

A few notes:

• w in Afrikaans sounds like English v
• aa is a long vowel
• the two oo sounds are pronounced clearly
• the stress is usually near the beginning

You will often hear it smoothly linked in speech, almost as one flowing word, which makes sense because it is written as one word.

Afrikaans often uses the simple present where English may use either:

• simple present: We know
• present continuous: they are talking

So:

• Ons weet waaroor hulle praat

can correspond naturally to English:

• We know what they talk about
• We know what they are talking about

In normal translation, what they are talking about is usually the best English rendering, but the Afrikaans uses the ordinary present form praat.