Die oplaaispoed is laag tydens die netwerkonderbreking.

Because the sentence contains two nouns, and each one is marked as definite:

• die oplaaispoed = the upload speed
• die netwerkonderbreking = the network interruption/outage

In Afrikaans, die is the definite article for both singular and plural nouns. Unlike English, it does not change form.

Oplaaispoed is a compound noun:

• oplaai = upload
• spoed = speed

So oplaaispoed literally means upload speed.

Afrikaans forms compounds very often, much like German and Dutch. English sometimes writes similar ideas as two words, but Afrikaans often joins them into one word.

This is normal Afrikaans main-clause word order:

• Die oplaaispoed = subject
• is = verb
• laag = complement/adjective

So it follows the common pattern:

subject + verb + rest

This is similar to English: The upload speed is low.

Because laag is being used after the verb is, so it is a predicate adjective.

In Afrikaans:

• die spoed is laag = the speed is low
• die lae spoed = the low speed

So:

• laag = basic form, often after is
• lae = inflected form, often before a noun

This is a very common pattern in Afrikaans adjectives.

Tydens means during.

It introduces a time phrase:

• tydens die vergadering = during the meeting
• tydens die storm = during the storm
• tydens die netwerkonderbreking = during the network interruption

So in your sentence, it tells you when the upload speed is low.

Yes. Netwerkonderbreking is another compound:

• netwerk = network
• onderbreking = interruption, disruption, outage

So netwerkonderbreking means network interruption, network disruption, or sometimes network outage, depending on context.

Afrikaans strongly prefers these compact compound nouns.

Yes, depending on context.

Literally, laag means low, so The upload speed is low is very close to the Afrikaans wording.

But in natural English, people often say:

• The upload speed is slow during the network outage
• Upload speed is low during the network interruption

So low is the direct match, while slow may sound more natural in some English contexts.

Yes. You can move the time phrase to the front:

Tydens die netwerkonderbreking is die oplaaispoed laag.

This still means the same thing: During the network interruption, the upload speed is low.

Notice that when the sentence begins with Tydens die netwerkonderbreking, the verb is still comes early in the clause. Afrikaans keeps the finite verb in the second position in main clauses.

Afrikaans does not have the kind of case system that German has, and it has far fewer noun ending changes than many European languages.

So after tydens, you simply use the noun phrase normally:

• tydens die les
• tydens die ete
• tydens die netwerkonderbreking

No article change is needed. Die stays die.

Usually it means the upload speed, but in real usage Afrikaans sometimes uses die in places where English might sound more general.

So depending on context, it could refer to:

• a specific upload speed being discussed, or
• upload speed in the situation at hand

In many technical or instructional contexts, Afrikaans uses die where English might also accept a more general phrasing such as Upload speed is low during the network interruption.

Sometimes, but the meaning shifts a little.

• laag = low
• stadig = slow

So:

• Die oplaaispoed is laag = The upload speed is low
• Die oplaai is stadig = The uploading is slow

If you are talking about a measured rate or bandwidth, laag is often a good fit. If you are talking about the process feeling slow, stadig may be more natural.

A rough guide would be:

dee OH-pleye-spoot is laagh TAY-dens dee NET-verk-ohn-der-BRAY-king

A few useful notes:

• die is usually like dee
• ui in tydens is not exactly an English sound, but TAY is a rough approximation
• g in laag is a throaty sound in Afrikaans, not a normal English g
• compounds are usually stressed on the first main part, though natural speech can vary

This is only an approximation, but it can help you get started.