Die watertoevoerslang is agter die wasmasjien.

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

So:

• water = water
• toevoer = supply / feed
• slang = hose / flexible tube

Together, watertoevoerslang means a water supply hose.

The same thing happens in wasmasjien:

• was = wash
• masjien = machine

So wasmasjien = washing machine.

A useful rule: in Afrikaans compounds, the last part is usually the main noun, and the earlier parts describe it.

Die means the.

It appears twice because there are two definite noun phrases in the sentence:

• Die watertoevoerslang = the water supply hose
• die wasmasjien = the washing machine

Unlike English learners might expect from German, Afrikaans does not have different forms of the for gender. It uses die for all genders, and also for plural definite nouns.

So you do not need to worry about masculine, feminine, or neuter articles here.

Also, die in Afrikaans is pronounced roughly like dee, not like the English verb die.

Yes. Is is the present-tense form of to be, and here it works very much like English is.

So the structure is:

• Die watertoevoerslang = subject
• is = verb
• agter die wasmasjien = location phrase

One nice thing about Afrikaans is that verbs do not change much according to the subject the way English verbs do. For example, is stays is.

Agter means behind.

It is a preposition, so it comes before the noun phrase that follows it:

• agter die wasmasjien = behind the washing machine

This works very similarly to English:

• behind the washing machine

So in the sentence, agter die wasmasjien tells you where the hose is.

This is the normal Afrikaans word order for a basic main clause:

Subject + verb + rest of the sentence

So:

• Die watertoevoerslang = subject
• is = verb
• agter die wasmasjien = place information

That is very close to English word order.

You can also move the location phrase to the front for emphasis:

• Agter die wasmasjien is die watertoevoerslang.

Notice that in Afrikaans main clauses, the finite verb stays in second position. That is a very important pattern.

A rough English-friendly guide is:

• Die ≈ dee
• watertoevoerslang ≈ VAH-ter-too-VOO-er-slahng
• is ≈ iss
• agter ≈ AKH-ter
• die ≈ dee
• wasmasjien ≈ vahs-ma-SHEEN

A few pronunciation notes:

• The g in agter is a guttural sound, like the ch in Scottish loch or German Bach.
• The Afrikaans w often sounds closer to an English v than an English w.
• sj in masjien sounds like English sh.

The exact accent will vary a bit by speaker, but those approximations will get you close.

No. Afrikaans is much simpler than German in this respect.

• There is no grammatical gender you need to mark with different definite articles.
• There are no case endings on die here.
• The nouns do not change form after agter.

So you can simply learn:

• die = the
• agter
  • noun phrase = behind + noun phrase

That simplicity is one of the reasons many learners find Afrikaans grammar approachable.

You would use ’n, which means a / an:

• ’n watertoevoerslang is agter die wasmasjien.

A few important notes about ’n:

• It is written with an apostrophe: ’n
• It is not capitalized in normal writing, even at the start of a sentence in many conventions; instead, the next word may be capitalized in titles or special formatting situations
• It is pronounced more like a weak uh sound

So:

• die watertoevoerslang = the water supply hose
• ’n watertoevoerslang = a water supply hose

You would make the noun plural, while die can still stay die:

• Die watertoevoerslange is agter die wasmasjien.
• The water supply hoses are behind the washing machine.

The plural of watertoevoerslang is watertoevoerslange.

If you also wanted to make washing machine plural, you could say:

• Die watertoevoerslange is agter die wasmasjiene.

So a useful point is:

• die can mean the for both singular and plural nouns

Yes, normally they are written as single compound nouns in standard Afrikaans.

That is different from English, where we often write similar expressions as separate words, such as:

• water supply hose
• washing machine

In Afrikaans, compounds are very commonly written solid:

• wasmasjien
• skottelgoedwasser
• huisdeur
• kombuistafel

So if you see a long noun in Afrikaans, it is often worth trying to split it into smaller meaningful parts. That is a very useful reading strategy.