Skakel Wi-Fi af en skakel mobiele data aan.

Because this is an imperative sentence, meaning a command.

In Afrikaans, just like in English, commands usually leave out the subject:

• Skakel Wi-Fi af. = Turn off Wi-Fi.
• (Jy) skakel Wi-Fi af. would normally mean You turn off Wi-Fi, not a command.

So the hidden subject is understood as you.

Here, skakel means switch or turn in the sense of operating a device or setting.

In technology-related language, Afrikaans often uses:

• aanskakel = switch on / turn on
• afskakel = switch off / turn off

So in this sentence, skakel works together with af and aan to express turn off and turn on.

They are the parts that give the meaning off and on.

• af = off
• aan = on

Together with skakel, they form verbs:

• afskakel = turn off
• aanskakel = turn on

This is similar to English phrasal verbs like turn off and turn on, where a small extra word changes the meaning of the verb.

Because in Afrikaans main clauses and commands, these verbs are often split.

The full verb is:

• afskakel
• aanskakel

But in a normal sentence or command, the main verb part comes earlier and the particle goes later:

• Skakel Wi-Fi af.
• Skakel mobiele data aan.

So the structure is roughly:

• verb + object + particle

This is a very common Afrikaans pattern.

Because the sentence really contains two commands joined by and:

• Skakel Wi-Fi af
• (en) skakel mobiele data aan

Afrikaans often repeats the verb in this kind of coordinated instruction, especially in clear step-by-step directions. It sounds natural and explicit.

If you did not repeat it, the sentence would feel incomplete or less standard in this context.

Because that is how these separable verb forms usually behave in Afrikaans main clauses.

With afskakel / aanskakel, the particle often moves to the end of that clause:

• Skakel Wi-Fi af
• Skakel mobiele data aan

So the object sits between the verb stem and the particle.

For an English speaker, it can help to think of it like this:

• skakel ... af = turn ... off
• skakel ... aan = turn ... on

Even though English can say both turn off Wi-Fi and turn Wi-Fi off, Afrikaans strongly prefers this split pattern here.

Because mobiele is an adjective placed before a noun, and Afrikaans adjectives often take an -e ending in that position.

• mobiel = mobile
• mobiele data = mobile data

So mobiele is the normal attributive form of the adjective before data.

In instructions like this, Afrikaans often leaves out articles when talking about settings or functions in a general way.

So:

• Skakel Wi-Fi af
• Skakel mobiele data aan

sounds natural in the same way English says:

• Turn off Wi-Fi
• Turn on mobile data

rather than Turn off the Wi-Fi in a phone-settings instruction.

Yes. En simply means and.

It joins the two commands:

• Skakel Wi-Fi af
• en
• skakel mobiele data aan

So the whole sentence is just two linked instructions.

The dictionary forms are usually written as one word:

• afskakel = to turn off
• aanskakel = to turn on

But in a command or ordinary main clause, they usually split:

• Skakel Wi-Fi af
• Skakel mobiele data aan

So when learning vocabulary, it is useful to remember both:

• the full dictionary form
• the split sentence pattern