Learn Hardcore Danish: Jeg læser ikke hele bogen på én gang.

In questions and some other structures the order can change, but in a normal declarative sentence the finite verb comes second and ikke normally comes right after it (before the main object and most adverbials).

Can I move ikke somewhere else, like Jeg læser hele bogen ikke på én gang?

For everyday neutral Danish, you should keep:

Jeg læser ikke hele bogen på én gang.

Other positions are either wrong or sound very marked/odd:

*Jeg læser hele bogen ikke på én gang.
→ This is not normal Danish; most natives would reject it.
*Jeg læser hele bogen på én gang ikke.
→ Also wrong/very strange in standard Danish.

There are a few advanced, special cases where ikke can move (for strong emphasis or contrast), but as a learner you should stick to:

subject – verb – ikke – (object / the rest)

for simple statements.

Why is it hele bogen and not hele bog or den hele bog?

Danish usually marks definiteness with a suffix on the noun:

bog = book
bogen = the book

With hele:

hele bogen = the whole book
(definite form on the noun, no den)

You cannot say:

*hele bog for the whole book → ungrammatical
*den hele bog for the whole book in this sense → sounds wrong/unnatural here

Compare:

en hel bog = a whole book (indefinite, any one book)
hele bogen = the whole book (a specific book both speaker and listener know about)

So hele bogen is the natural way to say the whole book in this sentence.

What is the difference between hele bogen and en hel bog?

They both involve the idea of a whole book, but:

hele bogen
= the whole book
→ Refers to a specific book already known in the conversation.
Example: Jeg læser ikke hele bogen på én gang.
I don’t read this particular book all in one go.
en hel bog
= a whole book / an entire book (indefinite)
→ Not a specific book; just one whole book.
Example: Jeg kan læse en hel bog på en dag.
I can read an entire book in a day.

In your sentence, we’re clearly talking about one specific book, so hele bogen is correct.

Could I just say Jeg læser ikke bogen på én gang without hele?

Yes, you can, but the nuance changes slightly.

Jeg læser ikke hele bogen på én gang.
→ Very explicit: you do not read the entire book in one go.
Jeg læser ikke bogen på én gang.
→ More neutral: I don’t read the book in one go.
It often still implies not the whole thing, but the idea of completeness is less strongly highlighted.

Using hele makes the “from start to finish in one go” idea very clear.

Why is the tense just læser? In English I’d say I’m not reading or I don’t read – which is it?

Danish uses the same present tense form for both simple and progressive meanings:

læser can mean:
- read(s) (general/habitual)
- am/are reading (right now / around this time)

So:

Jeg læser ikke hele bogen på én gang.
can mean:
- I don’t read the whole book at once (habit)
- I’m not reading the whole book at once (about a current reading situation)

Which one is meant is determined by context, not by the verb form. Danish does not have a built‑in -ing tense like English.

What exactly does på én gang mean, and can it also mean immediately?

på én gang literally means in one go / all at once. It’s about amount and simultaneity, not about time delay.

Jeg læser ikke hele bogen på én gang.
→ I don’t read the entire book in one single stretch / sitting.

It does not normally mean immediately as in right away. For immediately/right away, you would more often use:

med det samme
straks

Example difference:

Han spiste ikke hele kagen på én gang.
→ He didn’t eat the entire cake in one go (maybe in several portions).
Han spiste kagen med det samme.
→ He ate the cake immediately (as soon as he got it).

Why is én written with an accent? Can I just write en?

The accent in én is used to emphasize the number one, to distinguish it from the indefinite article en.

en = a / an (indefinite article)
én = one (single) (number, emphasized)

In på én gang, the idea is one single time / one single go, so the accent is common and helps readability:

på én gang = in one go (not two or three times)

You can see på en gang written without the accent (especially informally), and most Danes will still read it as the same expression, but på én gang is clearer and more standard.

Why is the preposition på used in på én gang, and not i or om?

Here på is part of a fixed idiomatic expression:

på én gang = in one go / all at once

Danish uses på in many time‑ and quantity‑related expressions where English might use in, for, or nothing:

på én gang – in one go
på samme tid – at the same time
to gange på en uge – twice in a week
på én dag – in one day

So in this phrase, på isn’t freely chosen; you simply memorize på én gang as a unit.

Why is the order hele bogen på én gang and not på én gang hele bogen?

Typical neutral order in Danish is:

verb – (ikke) – object – adverbial of time/manner/etc.

So we get:

… læser ikke hele bogen på én gang.
→ object: hele bogen
→ adverbial: på én gang

If you say *Jeg læser ikke på én gang hele bogen, it will sound odd or at best very marked and poetic. In everyday standard Danish, keep:

… (ikke) + object + time/manner phrase
→ ikke hele bogen på én gang

How do you pronounce the words læser, ikke, and bogen?

Approximate standard Danish pronunciation (Copenhagen‑like):

læser ≈ /ˈlɛːsɐ/
- læ- like “le” in “letter” but longer,
- -ser with a schwa‑like ending.
ikke ≈ /ˈeg̊ə/
- starts with a short e,
- g is soft (almost like a very weak g),
- ending is a schwa (like the a in “sofa”).
bogen ≈ /ˈb̥oːən/
- bo- like “bo” in “boat”, but with a longer vowel,
- final -en is reduced, very light.

Danish reduces many unstressed endings, so the last syllables are usually quite weak compared to English.

Does læser only mean to read, or can it also mean to study?

læse primarily means to read, but in Danish it is also commonly used in the sense of to study (at a school/university).

Examples:

Jeg læser en bog.
→ I’m reading a book.
Jeg læser medicin.
→ I study medicine (at university).

In your sentence:

Jeg læser ikke hele bogen på én gang.
the meaning is clearly to read a book, not to study at university.

How would I say this sentence in the past or in the future?

You mainly change the verb form (and add a helper verb for future if needed):

Past (simple):

Jeg læste ikke hele bogen på én gang.
→ I didn’t read the whole book in one go.

Future with intention (using vil):

Jeg vil ikke læse hele bogen på én gang.
→ I will not read / I’m not going to read the whole book in one go.

Near future with a time expression:

I morgen læser jeg ikke hele bogen på én gang.
→ Tomorrow I won’t read the whole book in one go.

The rest of the sentence (ikke hele bogen på én gang) stays the same; you mainly adjust the verb.