Die voetoorgang en stopteken is duidelik.

Die is the definite article in Afrikaans, the equivalent of the.

A few useful things about die:

• It is used for both singular and plural nouns.
• It does not change for grammatical gender.
• So Afrikaans keeps this part simpler than languages that have different forms for the.

In this sentence, die marks the noun phrase as definite: you are talking about a specific crossing and stop sign.

In Afrikaans, one article can cover two nouns joined by en if they belong together in the same phrase:

die voetoorgang en stopteken

That is normal. You can also repeat the article:

die voetoorgang en die stopteken

Both are possible. Repeating die can sound a bit more explicit, but using it only once is perfectly natural.

Because Afrikaans does not change the present-tense form of to be the way English does.

You get:

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

So is works for both singular and plural subjects. English switches between is and are, but Afrikaans keeps is.

Here duidelik comes after is, so it is a predicative adjective. In that position, Afrikaans adjectives usually stay in their basic form:

• Die stopteken is duidelik.
• Die voetoorgang is duidelik.

But before a noun, an adjective is usually attributive, and then it often takes -e:

• die duidelike stopteken
• die duidelike voetoorgang

So:

• after is → duidelik
• before a noun → usually duidelike

Afrikaans strongly prefers compound nouns written as single words.

So:

• voet
  • oorgang → voetoorgang
• stop
  • teken → stopteken

English often writes similar ideas as two words or with an adjective + noun structure, but Afrikaans usually joins them into one compound noun.

This is a very common feature of Afrikaans, so getting used to compounds is important.

En simply means and.

It joins the two nouns:

• voetoorgang
• stopteken

So the subject is a coordinated phrase: the crossing and stop sign. The adjective duidelik then describes that combined subject.

The structure is:

Subject + verb + complement

So here:

• Die voetoorgang en stopteken = subject
• is = verb
• duidelik = complement/adjective

This is very similar to English word order in a simple statement like The crossing and stop sign are clear.

Because Afrikaans does not capitalize all nouns.

Unlike German, Afrikaans only capitalizes:

• the first word of a sentence
• proper nouns

So in this sentence:

• Die is capitalized because it begins the sentence.
• voetoorgang, stopteken, and duidelik stay lowercase.

Yes. If duidelik comes before the noun, it usually changes to duidelike:

• die duidelike voetoorgang
• die duidelike stopteken

So you could say something like:

Die duidelike voetoorgang en stopteken ...

But in your original sentence, duidelik comes after is, so it stays duidelik.

This is one of the most common adjective patterns Afrikaans learners need to notice.

Yes. In this sentence, duidelik applies to the whole coordinated subject, so it describes both voetoorgang and stopteken.

In other words, the sentence says that both items are clear/clearly visible. The adjective is not limited to only the second noun.