Gister kon ek nie goed slaap nie, omdat ek 'n verkoue gehad het.

Because Afrikaans follows a verb-second pattern in main clauses.

If you put Gister ("yesterday") first for emphasis or normal time-setting, the finite verb must come next:

• Gister kon ek nie goed slaap nie.

So the order is:

• Gister = first element
• kon = second element, the finite verb
• ek = subject

If you started with the subject instead, you would get:

• Ek kon gister nie goed slaap nie.

Both are correct, but the emphasis is slightly different.

Kon is the past tense of kan.

• kan = can / am able to
• kon = could / was able to

So:

• Ek kan slaap. = I can sleep.
• Ek kon slaap. = I could sleep.

In your sentence, kon shows that this is about the past: yesterday, the speaker could not sleep well.

Afrikaans often uses double negation:

• nie ... nie

In this sentence:

• Gister kon ek nie goed slaap nie

The first nie comes after the verb part and starts the negation. The second nie closes the clause.

So the pattern is roughly:

• subject + verb + nie
  • rest + nie

Here it means:

• could not sleep well

This double nie is one of the most important features of standard Afrikaans.

Yes, goed often means good, but in Afrikaans it is also commonly used where English would use well.

So:

• goed slaap = sleep well

This is very normal Afrikaans.

For an English speaker, it can feel strange because English distinguishes:

• good (adjective)
• well (adverb)

Afrikaans often uses goed in places where English would prefer well.

Because after a modal verb like kan/kon, Afrikaans uses the bare infinitive:

• kan slaap
• kon slaap

So:

• Ek kan slaap. = I can sleep.
• Ek kon slaap. = I could sleep.

You do not use geslaap here, because geslaap is the past participle form used in perfect constructions such as:

• Ek het goed geslaap. = I slept well / I have slept well.

But with kon, the normal form is just slaap.

Because omdat ("because") introduces a subordinate clause, and subordinate clauses in Afrikaans usually send the verbs to the end.

Main clause word order:

• Ek het 'n verkoue gehad. = I had a cold.

After omdat:

• omdat ek 'n verkoue gehad het

Notice how the verb parts move to the end.

Also, in the perfect tense, Afrikaans commonly has:

• past participle + auxiliary at the end

So:

• gehad het

This is completely normal after omdat.

'n is the Afrikaans indefinite article, meaning a or an.

So:

• 'n verkoue = a cold

A few important things about 'n:

• It is always written in lowercase, even if it begins a sentence.
• It has an apostrophe because it is a reduced form.
• In speech, it is usually pronounced very lightly, like a schwa sound.

Example:

• Ek het 'n boek. = I have a book.
• 'n Man wag buite. = A man is waiting outside.

Even at the start of a sentence, it stays 'n, not 'N.

Yes. Afrikaans, like English, normally uses have with illnesses such as a cold:

• Ek het 'n verkoue. = I have a cold.
• Ek het 'n verkoue gehad. = I had a cold.

So in your sentence:

• omdat ek 'n verkoue gehad het
• because I had a cold

This is a very natural way to express being ill in Afrikaans.

Yes.

For example:

• Gister kon ek nie goed slaap nie.
• Ek kon gister nie goed slaap nie.

Both are correct.

The difference is mostly about emphasis and style:

• Gister first: sets the time immediately, often very natural in storytelling
• Ek first: starts with the subject, also very common

What you cannot do in a normal main clause is ignore the verb-second rule. So if Gister is first, the finite verb should still come second:

• Gister kon ek ... ✅
• Gister ek kon ... ❌

The comma separates the main clause from the subordinate clause:

• Gister kon ek nie goed slaap nie, omdat ek 'n verkoue gehad het.

This helps show that the second part explains the reason:

• because I had a cold

In writing, this comma is standard and makes the sentence easier to read.