Learn Hardcore Norwegian: Vi må ta hensyn til tiden, ellers rekker vi ikke toget. - We must take the time into consideration, otherwise we won’t catch the train.

Ta hensyn til is a fixed expression meaning to take into account / to consider.
Word-for-word it’s like take consideration to, which doesn’t map neatly to natural English, so it’s best learned as a chunk:

å ta hensyn til + noun = to take account of + noun
Examples:
Ta hensyn til været. = Consider the weather.
Hun tar hensyn til barna. = She takes the children into account / is considerate of the children.

(You’ll also see the noun hensyn used in other set phrases, but ta hensyn til is the most common.)

Why is it hensyn and not et hensyn / hensynet?

In ta hensyn til, hensyn is typically used as an uncountable, idiomatic noun (more like “consideration” in general), so it often appears without an article.
You can use the countable form when you mean “a consideration/a factor”:

et hensyn = a consideration (one specific factor)
flere hensyn = several considerations

But in the idiom ta hensyn til, the bare form hensyn is the standard choice.

What is the grammar of må here—does it mean “must” or “have to”?

Må is the present tense of the modal verb å måtte and commonly means must / have to / need to, depending on context.
In this sentence, Vi må … is most naturally We have to / We need to … (practical necessity), though “must” can also work in English.

Structure:

Vi må
- infinitive verb phrase
Vi må ta hensyn … (the main verb after må stays in the infinitive: ta)

Why is it til tiden with the definite form tiden instead of til tid?

Norwegian often uses the definite form when talking about something understood as specific in context—here, the time (i.e., the schedule / the time we have).
So tiden is “the time” in a general-but-contextually-defined sense.

tiden = the time (the relevant time available / time constraints)
You could also see:
ta hensyn til tid in more abstract or technical phrasing, but til tiden is the natural everyday version here.

What does ellers do in the sentence, and where can it be placed?

Ellers here means otherwise / or else and introduces a consequence if the first part isn’t followed.

Placement: it often comes at the start of the second clause:

..., ellers rekker vi ikke toget.

You can also see:

Ellers rekker vi ikke toget. (as its own sentence)
Hvis ikke, rekker vi ikke toget. (similar meaning, different structure)

Why is there a comma before ellers?

Because ellers introduces a new clause, and Norwegian normally separates two main clauses with a comma (especially when the second one is introduced by a linking word like ellers).

So the pattern is:

main clause, comma, main clause

What does rekker mean, and why isn’t it klarer or når?

Rekker (from å rekke) commonly means to have time to / to make it in time / to manage in time.

å rekke toget = to catch the train (in time)

Compared to similar verbs:

å klare = to manage (ability/difficulty), not specifically about time
å nå = to reach (physical arrival), can be used but rekke highlights time sufficiency

So rekker is the most precise for “will we make it in time?”.

Why is it rekker vi ikke toget (verb before subject) instead of vi ikke rekker toget?

Norwegian is a V2 language: in main clauses, the finite verb is normally in the second position.

In the second clause, ellers takes the first position, so the verb comes next:

Ellers (position 1) + rekker (position 2) + vi
- ikke
  - toget

If the clause started with vi, you’d get:

Vi rekker ikke toget.

Where does ikke go, and can it move around?

In a normal main clause, ikke typically comes after the finite verb and usually after the subject:

Vi rekker ikke toget.
Ellers rekker vi ikke toget.

You generally can’t place ikke before the verb in standard word order (that would sound non-native or be used only in special emphatic styles).

Why is it toget (definite) instead of et tog?

Toget is the definite form: the train. In context, it’s understood which train you mean (the one you intend to take). Norwegian commonly uses the definite form in exactly this “shared context” situation.

If you said et tog, it would be more like a train (some train or other), which is usually not what you mean when you’re trying to catch a specific departure.

Is å rekke toget the most natural way to say “catch the train,” and are there alternatives?

Å rekke toget is very natural when the focus is time (“make it in time”). Other common options:

å rekke å ta toget = to have time to take the train
å nå toget = to reach the train (less explicitly about time)
å komme seg på toget = to get onto the train (emphasis on boarding)

For “We won’t make the train (in time),” Vi rekker ikke toget is one of the most idiomatic choices.

How would the sentence change in a more formal or more casual style?

This sentence is already neutral and common. Some variations:

More formal / explicit:

Vi må ta hensyn til tiden, ellers rekker vi ikke å ta toget. (adds ikke å ta = “won’t have time to take”)

More casual:

Vi må skynde oss, ellers rekker vi ikke toget. = We have to hurry, otherwise we won’t catch the train.
Vi må passe på tiden, ellers rekker vi ikke toget. = We have to watch the time, otherwise we won’t catch the train.