Ons handig die aansoekvorm vir die vakature aanlyn in.

Because the full verb is inhandig, which means to hand in / to submit. In a main clause in Afrikaans, many verbs with prefixes like in-, op-, uit-, etc. are separable.

So:

• infinitive: inhandig
• main clause: Ons handig ... in

That is why in moves to the end of the clause.

Compare:

• Ek wil die vorm inhandig. = I want to submit the form.
• Ek handig die vorm in. = I submit the form.

This is very similar to English hand in.

Not usually in this sentence. Here handig is just the main part of the separable verb inhandig.

Also, be careful: handig is very commonly an adjective meaning handy / useful / convenient.

For example:

• Dit is baie handig. = That is very handy.

So in Ons handig ... in, you should understand handig ... in together as the verb.

That is normal Afrikaans word order for a separable verb in an ordinary statement.

Afrikaans main clauses usually put the finite verb in the second position, and the separable prefix/particle goes to the end.

Structure here:

• Ons = subject
• handig = finite verb
• die aansoekvorm vir die vakature = object phrase
• aanlyn = adverb
• in = separable particle

So the sentence pattern is completely normal: Ons handig die aansoekvorm vir die vakature aanlyn in.

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

So you get:

• Ek handig in
• Jy handig in
• Hy handig in
• Ons handig in
• Hulle handig in

This is much simpler than English, where you have I submit but he submits.

Aansoekvorm means application form.

It is a compound noun:

• aansoek = application
• vorm = form

Afrikaans, like Dutch and German, very often writes compound nouns as one word.

Other examples:

• huiswerk = homework
• toegangskaartjie = admission ticket
• paspoortfoto = passport photo

So aansoekvorm is perfectly normal Afrikaans spelling.

It means for the vacancy.

Parts:

• vir = for
• die = the
• vakature = vacancy / job opening

So die aansoekvorm vir die vakature means the application form for the vacancy.

This tells you what kind of application form it is: the form connected to that specific job opening.

Using die means the vacancy is specific and already known from context: the vacancy.

If you said 'n vakature, it would mean a vacancy, more general or not previously identified.

Compare:

• vir die vakature = for the vacancy
• vir 'n vakature = for a vacancy

So the sentence suggests a particular vacancy is being talked about.

Aanlyn means online.

It tells you how or where/by what method the form is being submitted.

So:

• Ons handig die aansoekvorm in. = We submit the application form.
• Ons handig die aansoekvorm aanlyn in. = We submit the application form online.

Its placement is natural in Afrikaans. Adverbs like this often appear before the final separable particle.

Yes. Indien is another very common verb meaning to submit.

So these are both possible:

• Ons handig die aansoekvorm aanlyn in.
• Ons dien die aansoekvorm aanlyn in.

In many contexts, indien sounds a bit more formal or administrative, while inhandig can feel a little more like hand in/turn in, though both are widely understood.

In this sentence, it most naturally attaches to aansoekvorm.

So the meaning is:

• the application form for the vacancy

not:

• we submit the form for the sake of the vacancy

In other words, vir die vakature describes which form it is.

Because this is a normal main clause, not an infinitive construction.

You use om ... te with infinitives in certain structures, for example:

• Ons probeer om die aansoekvorm aanlyn in te handig. = We try to submit the application form online.

But in the actual sentence, the verb is already finite:

• Ons handig die aansoekvorm aanlyn in.

So no om is needed.

Yes, some parts can move, but the basic grammar must still work.

For example, you could say:

• Ons handig die aansoekvorm vir die vakature aanlyn in.
• Aanlyn handig ons die aansoekvorm vir die vakature in.

If you move aanlyn to the front, then the verb still has to stay in second position:

• Aanlyn = first element
• handig = second element
• ons = then the subject

That is a key Afrikaans rule in main clauses.

It sounds mostly neutral and perfectly normal.

A few notes:

• aansoekvorm
• vakature
• aanlyn
• inhandig

all fit well in administrative or workplace language.

If you wanted something a little more formal, indien might be chosen instead of inhandig, but the sentence as given is completely natural.