Die sitplek is naby die verhoog.

Because die is the definite article, meaning the.

In Afrikaans, die is used for:

• singular nouns: die sitplek = the seat
• plural nouns: die sitplekke = the seats
• all grammatical genders

So Afrikaans does not change the word for the the way some languages do. In this sentence, both sitplek and verhoog are definite, so both take die.

Yes. Afrikaans very often forms compound nouns as a single word.

So:

• sit = sit
• plek = place

Together, sitplek literally means sitting place, i.e. seat.

This is very normal in Afrikaans. English often writes similar ideas as two words or with a different fixed word, but Afrikaans commonly joins them:

• sitkamer = living room / sitting room
• badkamer = bathroom
• slaapkamer = bedroom

Here, naby means near and functions like a preposition.

So:

• naby die verhoog = near the stage

It can also appear in slightly different structures in other sentences, but in this sentence you can treat it simply as near.

You may also see naby aan in some contexts, but naby die verhoog is completely normal.

Because this is a simple main clause, and Afrikaans often looks quite similar to English in basic statements.

The structure is:

• Die sitplek = subject
• is = verb
• naby die verhoog = complement / location phrase

So it follows the pattern:

Subject + verb + rest

That said, Afrikaans has an important verb-second tendency in main clauses. In this sentence, the subject comes first, so the verb naturally comes second:

• Die sitplek is naby die verhoog.

If another element comes first, the verb still stays in second position:

• Naby die verhoog is die sitplek.

That version is less neutral, but it shows the pattern.

In this sentence, yes: is is the present-tense form of to be.

So:

• Die sitplek is naby die verhoog. = The seat is near the stage.

But one useful difference to remember is that Afrikaans does not usually use is to form a continuous tense the way English does with is walking, is eating, and so on. Afrikaans usually uses the simple present or another construction instead.

So in this sentence, is is just the ordinary linking verb.

A rough English-friendly guide is:

• sitplek ≈ sit-plek
• naby ≈ nah-bay
• verhoog ≈ fer-HOOKH or fer-HOAKH
  The final g is not a hard English g. It is the guttural Afrikaans sound also heard in Dutch-like pronunciations.

A few pronunciation notes:

• v in Afrikaans is often pronounced closer to English f
• y in naby sounds like the vowel in day
• g in verhoog is one of the sounds English speakers usually need to practise

In this sentence, yes, verhoog is a noun meaning stage.

A learner may notice that verhoog can also be a verb in Afrikaans meaning increase or raise, depending on context. But here it is clearly a noun because it comes after die:

• die verhoog = the stage

So the article tells you you are dealing with a noun here.

Because Afrikaans does not capitalize all nouns.

Unlike German, Afrikaans only capitalizes:

• the first word of a sentence
• proper names
• certain special cases like titles

So in:

• Die sitplek is naby die verhoog.

only Die is capitalized because it starts the sentence.
Both sitplek and verhoog are common nouns, so they stay lowercase.

Yes, but it changes the meaning slightly.

• naby die verhoog = near the stage
• by die verhoog = at / by the stage

Naby emphasizes closeness.
By is more general and can mean at, by, or next to, depending on context.

So if you specifically want near, naby is the best choice.

You would usually change sitplek to sitplekke:

• Die sitplekke is naby die verhoog.
• The seats are near the stage.

Notice two useful things:

• die stays die
• is also stays is

So Afrikaans is simpler than English here:

• English: the seat is / the seats are
• Afrikaans: die sitplek is / die sitplekke is

A very literal word-by-word breakdown is:

• Die = the
• sitplek = seat
• is = is
• naby = near
• die = the
• verhoog = stage

So the structure maps very neatly onto English in this case, which makes it a good beginner sentence.