Learn Hardcore Danish: Jeg kommer til at arbejde sent i dag. - I am going to end up working late today.

It expresses a likely or expected outcome in the (near) future—roughly “is going to” or “will end up.” So Jeg kommer til at arbejde sent i dag = “I’m going to end up working late today,” with a nuance that it feels inevitable rather than a deliberate plan.

Could I use skal or vil instead? What’s the difference?

Jeg skal arbejde sent i dag: duty/arrangement/agenda (“I’m scheduled/obliged to work late today”).
Jeg vil arbejde sent i dag: intention/willingness (“I want/intend to work late today”). As a future marker, vil often sounds like desire rather than prediction.
Jeg arbejder sent i dag: simple present for a plan/timetable (“I’m working late today”).
Jeg kommer til at arbejde sent i dag: expected outcome/inevitability (“I’ll end up working late today”).

Does komme til at also mean “accidentally”?

Yes—in the past tense it very often means “accidentally/unintentionally.”

Jeg kom til at slette filen = “I accidentally deleted the file.” In the present/future, kommer til at normally signals a prediction:
Det kommer til at regne = “It’s going to rain.”

Why is kommer in second position? Is that a rule?

Yes. Danish main clauses are V2 (the finite verb is in the second slot). In Jeg kommer til at arbejde…, the subject Jeg is first and the finite verb kommer is second. If you front a time word, the verb still stays second:

I dag kommer jeg til at arbejde sent.

Where does negation (ikke) go?

After the finite verb.

Jeg kommer ikke til at arbejde sent i dag.
Adverbs like sandsynligvis, nok, aldrig also go there:
Jeg kommer sandsynligvis/nok/aldrig til at arbejde sent i dag.

Why is it sent and not sen?

Because it’s an adverb modifying the verb arbejde. The adverb form is sent. As an adjective, the forms are: sen (common gender), sent (neuter), sene (plural/definite). Examples:

Adverb: Jeg arbejder sent.
Adjective: en sen middag, et sent tog, de sene nyheder.

Can I just say Jeg arbejder sent i dag?

Yes. It’s natural and means you’re working late today (plan/schedule). Jeg kommer til at arbejde sent i dag adds the nuance that circumstances will make it happen—it feels predicted or unavoidable.

Is i dag one word or two?

Two: i dag. Standard Danish writes it as two words. Similarly: i morgen (tomorrow), i går (yesterday), i aften (this evening).

Is komme til at the same as ende med at?

They overlap but aren’t identical.

Jeg kommer til at arbejde sent i dag: prediction/expectation.
Jeg ender med at arbejde sent i dag: “I end up working late today,” with a stronger sense of result after a process, sometimes with a hint of frustration.

Can I front the time or the adverb “late”?

Yes—just keep V2:

I dag kommer jeg til at arbejde sent.
Sent i dag kommer jeg til at arbejde. You can also front longer time phrases: Senere i dag kommer jeg til at arbejde.

How do you pronounce the sentence (roughly)?

Very approximate English-friendly hints:

Jeg ≈ “yai”
kommer ≈ “KOM-uh” (the final -er is a light, reduced ‘uh’)
til at ≈ “til a” (the at is often reduced to a short “a”)
arbejde ≈ “AR-bye-deh” (the d is a soft sound, like the “th” in “this,” but gentler)
sent ≈ “sayn(t)” with a long vowel
i dag ≈ “ee day” Spoken Danish reduces and blends a lot; don’t worry if it sounds “mumbled” at first.

Is arbejde here a verb or a noun?

A verb (the infinitive after til at): at arbejde = “to work.”
As a noun, it means “work/job”: mit arbejde = “my job,” et arbejde = “a job.”

How do I make a yes/no question from this?

Invert subject and verb:

Kommer du til at arbejde sent i dag? = “Are you going to work late today?”
Alternatives:
Skal du arbejde sent i dag? (schedule/obligation)
Vil du arbejde sent i dag? (do you want/intend to)

How would I say it in the past?

Neutral past: Jeg arbejdede sent i går. = “I worked late yesterday.”
Necessity: Jeg blev nødt til at arbejde sent i går. = “I had to work late yesterday.”
Accidental/result: Jeg kom til at arbejde sent i går. = “I (ended up/accidentally) worked late yesterday.” This can imply it wasn’t intended.

Where do modal adverbs like “probably” go?

Right after the finite verb:

Jeg kommer nok/sikkert til at arbejde sent i dag.
With måske (“maybe”), you typically put it first or after the subject:
Måske kommer jeg til at arbejde sent i dag. / Jeg måske kommer… (the first is more common/natural).

Do I have to keep kommer til at together?

No. The finite verb kommer is separate, and elements like ikke or nok go after it. You can’t drop til at, but you can split the sequence:

Jeg kommer bestemt/ikke/nok/sandsynligvis til at arbejde sent i dag.

Does sent i dag ever mean “tonight”?

It means “later today.” If you specifically mean “tonight,” use:

i aften (this evening/tonight)
i nat (tonight/at night)
Examples: Jeg arbejder i aften = “I’m working tonight.” Jeg arbejder sent i dag = “I’m working late today (later in the day).”