Die aanbouing is op die bouplan.

Because die is the Afrikaans definite article, meaning the.

Afrikaans uses die for:

• singular nouns
• plural nouns
• all grammatical genders

So unlike some other languages, you do not change the article depending on gender. In this sentence:

• Die aanbouing = the extension
• die bouplan = the building plan / blueprint

Aanbouing usually means an extension, an added-on part of a building, or an annex.

It comes from the idea of building onto something existing. So it is not just any building feature; it usually refers to something added to an original structure.

Depending on context, English translations might include:

• extension
• addition
• annex

Yes. Bouplan is a compound noun:

• bou = build / building
• plan = plan

Together, bouplan means building plan, construction plan, or blueprint, depending on context.

Afrikaans very often writes compound nouns as a single word, where English may use:

• one word
• two words
• or a hyphenated form

So bouplan as one word is completely normal.

This is the normal word order for a simple Afrikaans statement:

Subject + verb + rest

Here:

• Die aanbouing = subject
• is = verb
• op die bouplan = prepositional phrase

So the structure is very similar to English:

• The extension is on the building plan.

Afrikaans main clauses usually put the finite verb in the second position, and this sentence follows that pattern naturally.

Yes, op usually means on, and here it works much like English.

op die bouplan means on the building plan / on the blueprint.

This is idiomatic because drawings, plans, and documents are often thought of as flat surfaces, so something can be on them.

Examples:

• Dit is op die lys. = It is on the list.
• Die fout is op die bladsy. = The mistake is on the page.

Yes. In Afrikaans, the verb wees (to be) has the present-tense form is in ordinary statements for all persons.

So you get:

• Ek is = I am
• Jy is = you are
• Hy is = he is
• Ons is = we are
• Hulle is = they are

That is much simpler than English, which changes between am, is, and are.

No. Afrikaans does not capitalize all nouns.

So in this sentence:

• aanbouing is lowercase
• bouplan is lowercase

You only capitalize at the beginning of the sentence or for proper nouns, such as names of people, places, languages in some contexts, and so on.

A rough pronunciation guide for an English speaker:

• aanbouing ≈ AHN-boh-ing
• bouplan ≈ boh-PLAN

A few useful notes:

• aa is a long open vowel, somewhat like the vowel in father
• ou in bou is often like the o in go, though exact pronunciation depends on accent
• ui in Afrikaans can be tricky, but here the ending -ing is fairly straightforward

A rough full sentence pronunciation: Die aanbouing is op die bouplan ≈ Dee AHN-boh-ing is op dee boh-PLAN

Yes, you could, if the context already makes it clear that you mean a building plan. But bouplan is more specific.

Compare:

• die plan = the plan
• die bouplan = the building plan / blueprint

So if you want to avoid ambiguity, bouplan is the better choice.

A natural plural version would be:

Die aanbouings is op die bouplanne.

That means: The extensions are on the building plans.

Notice two useful Afrikaans features here:

1. die stays the same in the plural

   • die aanbouing = the extension
   • die aanbouings = the extensions

2. is also stays the same
   Afrikaans verbs do not change in the present tense the way English verbs do.

Not always. Afrikaans may also use other words depending on the exact meaning.

For example:

• aanbouing = a built-on addition or annex
• uitbreiding = an extension, enlargement, or expansion more generally

So if you are talking specifically about an added structure to a building, aanbouing is a good choice. If you are talking more generally about expansion, uitbreiding may be more appropriate.