Apen spiser en banan.

Ape is the basic dictionary form, meaning monkey / ape.

Apen is the definite singular form, meaning the monkey.
In Norwegian, the definite article is often added to the end of the noun as a suffix.

• ape = a monkey / monkey
• apen = the monkey

So Apen spiser en banan literally has the monkey as its subject.

Because en here is the indefinite article, like English a.

• en banan = a banana
• bananen = the banana

Norwegian usually shows:

• indefinite: article + noun
  
  • en banan
• definite: noun + ending
  
  • bananen

So in this sentence:

• apen = the monkey
• en banan = a banana

Spiser is the present tense of the verb å spise, meaning to eat.

So:

• å spise = to eat
• spiser = eat / eats / am eating / is eating depending on context

Norwegian verbs do not change for different persons the way English verbs do.

For example:

• jeg spiser = I eat
• du spiser = you eat
• han spiser = he eats
• de spiser = they eat

The verb stays spiser in all of them.

Yes, in this sentence the order is the straightforward subject + verb + object pattern:

• Apen = subject
• spiser = verb
• en banan = object

So it matches English very closely:

• The monkey eats a banana.

However, Norwegian also has an important V2 rule in many main clauses, meaning the verb often comes in the second position. This sentence already fits that naturally.

Because banan is a common-gender noun, so it takes en.

Norwegian nouns have grammatical gender. In Bokmål, the main options are:

• en for common gender
• et for neuter
• sometimes ei for feminine nouns

For banan, the standard form is:

• en banan
• bananen

Similarly, ape is also a common-gender noun:

• en ape
• apen

Good question. Norwegian ape can refer broadly to a monkey or ape, and in beginner materials it is often translated simply as monkey.

So even though English distinguishes ape and monkey more clearly, Norwegian ape is commonly used in a broader way. In a sentence like this, translating it as the monkey is completely natural.

A simple learner-friendly guide would be something like:

• Apen ≈ AH-pen
• spiser ≈ SPEE-ser
• en ≈ en or a weak ən
• banan ≈ bah-NAHN

A few helpful notes:

• The a in banan is not like the English a in day.
• The r at the end of spiser is usually light.
• Norwegian pronunciation varies somewhat by dialect, so exact sounds can differ.

Because Norwegian verbs are much simpler in this way than English verbs.

In English, you say:

• I eat
• he eats

But in Norwegian, the present tense stays the same:

• jeg spiser
• han spiser

So you do not need to memorize different present-tense endings for different subjects.

Then the definiteness would switch:

• En ape spiser bananen.

Compare:

• Apen spiser en banan. = The monkey eats a banana.
• En ape spiser bananen. = A monkey eats the banana.

This is a very useful pattern in Norwegian:

• en ape / apen
• en banan / bananen

The dictionary forms are:

• apen → ape
• spiser → å spise
• en → article, shown as en
• banan → banan

So if you looked the words up, you would usually find:

• ape = monkey / ape
• å spise = to eat
• banan = banana

That is why it is useful to recognize endings like -en in apen as grammar, not a completely different word.