Paien står på bordet.

Because Norwegian usually puts the definite article at the end of the noun.

• pai = pie
• paien = the pie
• bord = table
• bordet = the table

So instead of a separate word like English the, Norwegian often uses an ending:

• common gender singular: -en
• neuter singular: -et

That is why the sentence has paien and bordet, not a separate word for the.

Because the two nouns have different grammatical genders.

• en pai → paien
• et bord → bordet

In Bokmål, pai is a common gender noun, so its definite singular form takes -en.

bord is a neuter noun, so its definite singular form takes -et.

So the gender determines which definite ending you use.

Because paien already means the pie all by itself.

In English, you say:

• the pie

In Norwegian, you normally say:

• paien

You do not usually add another definite word before it unless you are doing something special, such as emphasis or using an adjective.

For example:

• paien = the pie
• den paien = more like that pie or that particular pie

Norwegian often prefers a position verb where English would simply use is.

Here, står comes from stå, meaning stand. Norwegian uses verbs like:

• stå = stand
• ligge = lie
• sitte = sit

These are often used to describe where something is located.

So Paien står på bordet is more specifically describing the pie as being placed there in a standing/upright/set way, rather than just saying that it exists there.

English usually says The pie is on the table, but Norwegian often chooses a more physical verb.

Yes, you can, but it is usually less natural if you are simply describing the location of a physical object.

• Paien er på bordet = neutral, general statement
• Paien står på bordet = more idiomatic if you are thinking of it as placed there
• Paien ligger på bordet = possible if you imagine it as lying flat

So er is not always wrong, but Norwegian often prefers stå / ligge / sitte when talking about location.

Because Norwegian present tense often covers both the English simple present and present progressive.

So:

• står can mean stands
• står can also mean is standing

The exact English translation depends on context.

This is very common in Norwegian. Another example:

• Han spiser = He eats or He is eating

Here, på means on.

So på bordet means on the table.

It is a very common preposition, but like English prepositions, it can be used in many different ways depending on the expression. In this sentence, it is the straightforward physical meaning: something is on a surface.

The word order is very straightforward:

• Paien = subject
• står = verb
• på bordet = place expression

So the pattern is:

subject + verb + location

That is a normal neutral main-clause word order in Norwegian.

You could also move the location to the front for emphasis:

• På bordet står paien.

That is still grammatical, but it sounds more marked or literary. The original sentence is the most neutral version.

You would use the indefinite forms:

• En pai står på et bord.

Compare:

• paien = the pie
• en pai = a pie
• bordet = the table
• et bord = a table

So the sentence you were given uses definite nouns, not indefinite ones.

A rough guide for an English speaker:

• Paien ≈ PIE-en
• står ≈ stohr
• på ≈ poh
• bordet ≈ BOR-deh

A few helpful notes:

• å is a rounded vowel, somewhat like the vowel in British more, though not exactly the same.
• paien has two parts: pai + en
• står has one syllable
• bordet has two syllables

As always, the exact sound depends on accent, but these approximations are good for getting started.