Die ultravioletlig is nodig.

Here die is the definite article, so it means the.

A useful thing to remember is that Afrikaans uses die for:

• singular nouns
• plural nouns
• all genders

So it is much simpler than languages that have several different words for the.

No. In Afrikaans, die is usually pronounced like dee.

So Die ultravioletlig is nodig starts with a dee sound, not an English die sound.

Afrikaans very often writes compound nouns as a single word.

So:

• ultraviolet
  • lig
• becomes ultravioletlig

English often leaves similar expressions as two words, but Afrikaans prefers to join them when they function as one noun.

In this sentence, the idea is being treated as one compound noun: ultravioletlig.

If you wanted to use ultraviolet as a separate adjective before lig, Afrikaans would normally use the adjective form ultraviolette, as in ultraviolette lig.

So the difference is:

• ultravioletlig = one compound noun
• ultraviolette lig = adjective + noun

Both express a similar idea, but the structure is different.

Afrikaans and English are related languages, so some very common words look alike. Is is one of them.

In Afrikaans, is is the present-tense form of wees (to be), and it is used with all persons:

• ek is
• jy is
• hy is
• ons is
• hulle is

So unlike English, you do not have forms like am / is / are. Afrikaans just uses is.

Nodig is an adjective here. It comes after the verb is and describes the subject.

So the structure is:

• Die ultravioletlig = subject
• is = linking verb
• nodig = adjective complement

This is similar to English sentences like:

• The light is necessary
• The light is needed

Because nodig comes after is.

In Afrikaans, adjectives usually stay in their basic form when they come after a linking verb like is:

• Die lig is nodig.

But when an adjective comes before a noun, it often takes -e:

• die nodige lig

So:

• after is → nodig
• before a noun → often nodige

Yes, you can.

The difference is roughly this:

• Die ultravioletlig is nodig. = The ultraviolet light is necessary
  This sounds more specific, as if both speaker and listener know which ultraviolet light is meant.

• Ultravioletlig is nodig. = Ultraviolet light is necessary
  This sounds more general.

So the article changes how specific the statement feels.

No, this is a very straightforward Afrikaans main clause.

The order is:

• subject
• verb
• complement

So:

• Die ultravioletlig = subject
• is = verb
• nodig = complement

A useful broader rule is that in Afrikaans main clauses, the finite verb usually comes second.

Afrikaans does not capitalize all nouns.

So unlike German, common nouns such as lig or ultravioletlig are normally written with a lowercase letter. The only reason Die starts with a capital letter here is that it is the first word of the sentence.

A rough pronunciation guide is:

dee uhl-tra-vy-oh-let-ləkh is NOH-dukh

A few notes:

• Die sounds like dee
• the g in lig and nodig is the throaty Afrikaans g, similar to the ch in Scottish loch
• the stress in nodig is usually on the first syllable

So if you say it slowly:

Die ... ultravioletlig ... is ... nodig

that will already get you quite close.