Δεν κοιμήθηκα καλά, γιατί είχε θόρυβο όλη νύχτα.

Κοιμήθηκα is the 1st person singular aorist of κοιμάμαι.

Even though κοιμάμαι looks like a middle/passive form, it has an active meaning: I sleep. Its normal past form is κοιμήθηκα = I slept.

In this sentence, the aorist is used because the speaker is talking about the night’s sleep as one complete past event:
Δεν κοιμήθηκα καλά = I didn’t sleep well.

In some contexts, κοιμήθηκα can also mean I fell asleep, but here, because of καλά and the rest of the sentence, it clearly means I slept.

This is a very common Greek aspect question.

• Δεν κοιμήθηκα καλά uses the aorist and means I didn’t sleep well overall.
• Δεν κοιμόμουν καλά uses the imperfect and means something more like I wasn’t sleeping well or I kept sleeping badly.

So:

• aorist = the whole event is viewed as a single completed whole
• imperfect = the action is viewed as ongoing, repeated, or in progress

In this sentence, the speaker is summarizing the whole night, so κοιμήθηκα is the natural choice.

Greek usually drops subject pronouns when they are not needed, because the verb ending already shows the person.

• κοιμήθηκα already means I slept
• so εγώ is unnecessary unless you want emphasis or contrast

For example:

• Δεν κοιμήθηκα καλά = neutral, natural
• Εγώ δεν κοιμήθηκα καλά = I didn’t sleep well, maybe implying someone else did

So leaving out εγώ is completely normal.

In Modern Greek, the usual adverb meaning well is καλά.

So:

• καλός = good
• καλά = well

Example:

• Μιλάει καλά ελληνικά = He/She speaks Greek well

Καλώς does exist, but it is mostly used in fixed expressions or more formal/literary language, such as:

• Καλώς ήρθατε = Welcome
• Καλώς έκανες = You did well / It was good that you did that

So in everyday Greek, Δεν κοιμήθηκα καλά is exactly what you would expect.

Γιατί can mean both:

• why
• because

The meaning depends on the sentence.

Here it introduces a reason: Δεν κοιμήθηκα καλά, γιατί είχε θόρυβο όλη νύχτα.
= I didn’t sleep well, because there was noise all night.

If it were a question, it could mean why:

• Γιατί δεν κοιμήθηκες καλά; = Why didn’t you sleep well?

So the structure and punctuation tell you which meaning is intended.

Yes. You could say:

Δεν κοιμήθηκα καλά, επειδή είχε θόρυβο όλη νύχτα.

That is also correct and natural.

In many contexts:

• γιατί = because
• επειδή = because / since

A rough difference is that επειδή can sound a little more explicit or slightly more formal, while γιατί is extremely common in everyday speech.

So both work, but γιατί is very normal here.

Yes, literally it does, but this is a very natural Greek pattern.

Greek often uses έχει in an impersonal way to mean something like:

• there is
• there was

Especially with things like:

• έχει ζέστη = it’s hot / there is heat
• έχει κίνηση = there is traffic
• έχει φασαρία = there is noise / commotion
• είχε θόρυβο = there was noise

So although είχε is the imperfect of έχω = have, the whole expression is best understood as there was noise.

Είχε is the imperfect of έχω.

It is used because the noise is presented as an ongoing background situation during the night. The speaker is not talking about one single moment when noise happened, but about a continuing condition.

So:

• είχε θόρυβο όλη νύχτα = there was noise all night

The imperfect is very common for background descriptions, ongoing states, and repeated situations in the past.

Because with έχει, the noun functions grammatically as the direct object, so it goes in the accusative.

That is why Greek says:

• έχει θόρυβο
• not έχει θόρυβος

Even though English translates this as there is noise, Greek is structurally using have.

So:

• θόρυβος = nominative
• θόρυβο = accusative

This is exactly what you would expect after έχει/είχε.

Because θόρυβο here means noise in general, not a specific identifiable noise.

Greek often leaves out the article with nouns used in a general, indefinite, or mass-noun sense, especially in expressions like this.

So:

• είχε θόρυβο = there was noise
• είχε έναν θόρυβο would suggest a more specific or particular noise
• είχε τον θόρυβο would sound like a known, specific noise already mentioned

Without the article, the sentence sounds natural and general.

Όλη νύχτα means all night.

Grammatically, this is an example of the accusative of duration/time span. Greek often uses the accusative to show how long something lasted.

So here:

• όλη νύχτα = for the whole night / all night

You will see the same pattern in expressions like:

• όλη μέρα = all day
• όλο το πρωί = all morning
• δύο ώρες = for two hours

Yes, absolutely.

Both are natural:

• όλη νύχτα
• όλη τη νύχτα

The version without the article is very common in adverbial time expressions and can feel slightly more compact or idiomatic.

The version with the article is also very common and fully correct.

So both of these work:

• είχε θόρυβο όλη νύχτα
• είχε θόρυβο όλη τη νύχτα

Yes. Greek word order is fairly flexible, although some orders are more neutral than others.

The original sentence:

Δεν κοιμήθηκα καλά, γιατί είχε θόρυβο όλη νύχτα.

is very natural and neutral.

But you could also say:

• Δεν κοιμήθηκα καλά γιατί όλη νύχτα είχε θόρυβο.
• Γιατί είχε θόρυβο όλη νύχτα, δεν κοιμήθηκα καλά.

These are possible, but they shift the emphasis a little.

So the original word order is probably the best one for a learner to remember first.

In writing, the comma is normal here because γιατί είχε θόρυβο όλη νύχτα is giving the reason for the first clause.

So:

• Δεν κοιμήθηκα καλά, γιατί είχε θόρυβο όλη νύχτα.

This punctuation helps show the sentence structure clearly.

In casual writing, people are not always consistent with commas, but in standard written Greek, the comma here is perfectly appropriate.