Jo flere flytteesker vi har, jo mer plass trenger vi.

It is a correlative comparison pattern, equivalent to English the more ..., the more ... or the more ..., the less ....

So:

• Jo flere flytteesker vi har, jo mer plass trenger vi
• The more moving boxes we have, the more space we need

This pattern is very common in Norwegian, and it works much like English:

• Jo eldre han blir, jo klokere blir han = The older he gets, the wiser he becomes
• Jo mindre du sover, jo trøttere blir du = The less you sleep, the more tired you get

Because Norwegian marks both parts of the comparison.

In English, we also do this:

• the more ..., the more ...

Norwegian does the same with jo:

• Jo flere ..., jo mer ...

The first jo introduces the first compared part, and the second jo introduces the result or corresponding second part.

Flere is the comparative form of mange (many).

So:

• mange = many
• flere = more

Because flytteesker is a countable plural noun (boxes), Norwegian uses flere:

• mange flytteesker = many moving boxes
• flere flytteesker = more moving boxes

You would not use mer here, because mer is generally used with uncountable nouns or amounts, not with countable plural things.

Because plass here means space, which is being treated as an uncountable noun.

So Norwegian uses:

• mer plass = more space

Compare:

• flere stoler = more chairs
• mer vann = more water
• mer tid = more time
• mer plass = more space

Plasser does exist, but it usually means places, spots, or seats, not space in this sense.

This is because of Norwegian word order, especially the V2 rule. In a main clause, the finite verb usually comes in the second position.

In the second part:

• jo mer plass is placed first
• then the verb trenger
• then the subject vi

So:

• jo mer plass trenger vi

This is normal Norwegian sentence structure.

If you said jo mer plass vi trenger, that would sound more like a subordinate clause pattern, and it is not the normal structure in this kind of jo ... jo ... sentence.

Flytteesker is the plural of flytteeske, which means moving box or packing box.

It is a compound noun:

• flytte = move / moving
• eske = box

Together:

• flytteeske = moving box
• flytteesker = moving boxes

Norwegian often forms this kind of idea as one single word, where English would often use two words.

Because Norwegian commonly writes compound nouns as one word.

So where English often writes:

• moving box
• car door
• summer house

Norwegian usually writes:

• flytteeske
• bildør
• sommerhus

This is a very important spelling habit in Norwegian. English speakers often want to separate the words, but in Norwegian they are usually combined.

Because plass is being used in a general, uncountable sense, like space in English.

Compare:

• Vi trenger plass = We need space
• Vi trenger mer plass = We need more space

You do not need an article here, just as English usually does not say we need a space when it means general room or capacity.

If plass meant a specific spot or seat, the structure could be different, but here it means general space.

Here are the main forms:

• jo = used in the jo ... jo ... comparison pattern
• flere = comparative of mange (many / more)
• flytteesker = plural of flytteeske
• vi = we
• har = present tense of ha (to have)
• mer = comparative of mye (much / more)
• plass = space, room
• trenger = present tense of trenge (to need)

So the sentence uses several ordinary dictionary words, plus a very common comparison structure.

Not really word-for-word. It is better to think of jo ... jo ... as one fixed pattern that corresponds to English the ... the ... in this special comparative structure.

So:

• Jo flere ..., jo mer ...
• The more ..., the more ...

But outside this structure, jo can have other uses too, so it is not a simple one-to-one translation of the.

Yes, the comma is standard here because the sentence has two linked clauses in the jo ... jo ... construction:

• Jo flere flytteesker vi har, jo mer plass trenger vi.

The comma helps separate the two compared parts clearly.

Yes, dess ... dess ... exists and means the same thing, but jo ... jo ... is usually the more common and natural choice in modern everyday Norwegian.

So:

• Jo flere flytteesker vi har, jo mer plass trenger vi = very common
• Dess flere flytteesker vi har, dess mer plass trenger vi = also correct, but often feels a bit more formal or literary

For most learners, jo ... jo ... is the safer pattern to remember and use.

No, not in normal standard Norwegian.

You need the subject in both clauses:

• Jo flere flytteesker vi har, jo mer plass trenger vi

Even though English sometimes feels flexible in comparison structures, Norwegian still needs the full clause structure here.

The singular noun is:

• en flytteeske = a moving box

The plural is:

• flytteesker = moving boxes

So the noun forms are:

• en flytteeske
• flytteesken
• flytteesker
• flytteeskene

In the sentence, the plural is used because flere naturally goes with a plural count noun.