Die sporthorlosie wys die hartklop.

Because die is the definite article, meaning the. In this sentence, both nouns are definite:

• die sporthorlosie = the sports watch
• die hartklop = the heart rate / the heartbeat

So Afrikaans uses die before both nouns, just as English would use the twice.

No. This is one of the nice things about Afrikaans.

Die is used for:

• singular nouns
• plural nouns
• all genders

So unlike languages that have different words for the depending on gender or number, Afrikaans keeps it simple.

Examples:

• die horlosie = the watch
• die horlosies = the watches

The article stays die.

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

So:

• sport
  • horlosie → sporthorlosie

This is completely normal. English often writes similar ideas as two words, but Afrikaans usually joins them.

Other examples:

• boekwinkel = bookshop
• huisdeur = front door / house door
• skooltas = school bag

Literally, hartklop is made up of:

• hart = heart
• klop = beat / knock

So the literal idea is heartbeat. But in real usage, especially with devices like watches or fitness trackers, hartklop can also refer to pulse or heart rate, depending on context.

In this sentence, with sporthorlosie, it most naturally refers to the heart-rate reading shown by the watch.

Wys means show, display, or sometimes point out, depending on context.

In the present tense, Afrikaans verbs usually do not change form for different subjects. That means the same verb form is used with I, you, he, she, it, we, and they.

Examples:

• Ek wys
• Jy wys
• Die sporthorlosie wys
• Ons wys

So wys stays wys.

Yes, in this simple main clause it is:

• Die sporthorlosie = subject
• wys = verb
• die hartklop = object

So the pattern is subject + verb + object, just like basic English word order.

However, Afrikaans has an important verb-second tendency in main clauses. If another element comes first, the verb still stays in second position:

• Vandag wys die sporthorlosie die hartklop.
  = Today the sports watch shows the heart rate.

So this sentence looks very English-like, but Afrikaans word order becomes more noticeably different in other sentence types.

Usually shows.

Afrikaans often uses the simple present where English might use either:

• shows
• is showing

So Die sporthorlosie wys die hartklop can describe a general fact or what the watch is displaying right now, depending on context.

If someone wants to be extra explicit about an ongoing action, Afrikaans can use a longer form, but in everyday language the simple present is very common and natural here.

A rough learner-friendly guide:

• die → dee
  Important: it is not pronounced like English die.

• wys → roughly vays
  The w in Afrikaans often sounds like an English v.

• sporthorlosie → roughly sport-hor-LO-see

• hartklop → roughly HART-klop

A few helpful notes:

• Afrikaans r is usually rolled or tapped more than in most English accents.
• g can be a throat sound, but there is no g in this sentence.
• Stress in sporthorlosie falls later in the word than an English speaker might expect.

Because Afrikaans does not capitalize all nouns the way German does.

Only these normally get capitals:

• the first word of a sentence
• proper names
• sometimes special titles or headings

So:

• Die is capitalized because it begins the sentence.
• sporthorlosie and hartklop stay lowercase because they are ordinary common nouns.

You would use ’n, the Afrikaans indefinite article:

• ’n sporthorlosie wys die hartklop.

A few useful things to know about ’n:

• It means a or an
• It is written with a small apostrophe-like mark before the n
• It is never capitalized in normal spelling, even at the beginning of a sentence
  For example: ’n Sporthorlosie wys die hartklop.

The plural of sporthorlosie is sporthorlosies.

So you could say:

• Die sporthorlosies wys die hartklop.

Notice two things:

1. die stays the same
2. the noun gets the plural ending -s

That is very typical in Afrikaans.