Hulle dans ewe vinnig.

Here, hulle means they. It is the subject of the sentence.

So:

• Hulle = they
• dans = dance
• ewe vinnig = equally fast / just as fast

In this sentence, hulle is doing the action.

Because Afrikaans verbs usually do not change form for different subjects in the present tense.

Compare:

• Ek dans = I dance
• Jy dans = you dance
• Hy/Sy dans = he/she dances
• Hulle dans = they dance

Unlike English, Afrikaans does not add an -s for he/she/it in the present tense.

Here it is a verb, meaning dance.

Afrikaans dans can also be a noun in other contexts, meaning a dance, but in Hulle dans ewe vinnig, it is clearly the action word because it comes after the subject hulle.

In this sentence, ewe means something like:

• equally
• just as
• to the same degree

So ewe vinnig means equally fast or just as fast.

It shows that the speed is the same.

Here vinnig is functioning as an adverb, because it describes how they dance.

• dans = the action
• vinnig = describes the action

English often uses -ly for adverbs, but Afrikaans usually does not. So the same word can often be used as both:

• 'n vinnige motor = a fast car
• Hy ry vinnig = He drives fast

So vinnig can be an adjective or an adverb depending on the sentence.

This is the normal word order for a simple main clause in Afrikaans:

• Subject
  • verb
    • the rest

So:

• Hulle = subject
• dans = verb
• ewe vinnig = adverbial phrase

Afrikaans main clauses usually keep the finite verb in the second position. This sentence follows that basic pattern very neatly.

Yes. Ewe usually suggests that something is the same as something else in degree.

So ewe vinnig often implies:

• they are as fast as someone else, or
• they are all dancing at the same speed

Sometimes the comparison is stated elsewhere, and sometimes it is just understood from context.

Yes, definitely. That is a very natural interpretation.

Hulle dans ewe vinnig can mean that they all dance at the same speed. In other words, none of them is dancing faster or slower than the others.

So the comparison does not always have to be with an outside person or group; it can be internal to they.

Yes. Net so vinnig is also natural and means just as fast.

There is a small nuance:

• ewe vinnig = equally fast / just as fast
• net so vinnig = just as fast

Both are possible, but ewe has a slightly more direct equal degree feel.

If you want to name the thing being compared, you could also say:

• Hulle dans net so vinnig soos ons. = They dance just as fast as we do.

Yes. It is in the present tense.

Depending on context, it can mean:

• a general fact: They dance equally fast
• a repeated/habitual action: They usually dance equally fast
• a current situation: They are dancing equally fast

Afrikaans often uses the simple present where English might use either dance or are dancing, depending on context.

No. Afrikaans does not form adverbs that way.

English:

• quick → quickly
• slow → slowly

Afrikaans usually keeps the same form:

• vinnig = fast / quickly
• stadig = slow / slowly

So vinnig is already the correct form in Hulle dans ewe vinnig.