Skadedyret spiser bladene.

Because Norwegian usually puts definiteness on the noun itself.

• et skadedyr = a pest
• skadedyret = the pest

The ending -et is the definite ending for many neuter singular nouns.

So:

• skadedyr = pest
• skadedyret = the pest

Unlike English, Norwegian often does not need a separate word like the in simple noun phrases.

It is made up of:

• skade = damage, harm
• dyr = animal
• together: skadedyr = pest, vermin, harmful creature
• -et = the definite ending

So literally it is something like the harmful animal, but the natural English translation is the pest.

Also, the gender of a compound noun usually comes from the last part, and dyr is a neuter noun, which is why we get et skadedyr and skadedyret.

Because bladene means the leaves, while blad on its own is just leaf/leaves depending on context.

Here is the pattern:

• et blad = a leaf
• blad = leaves / leaf in some contexts
• bladene = the leaves

The ending -ene is a very common definite plural ending in Norwegian.

So the sentence is talking about specific leaves, not just leaves in general.

For the same reason as with skadedyret: Norwegian often marks the by adding an ending to the noun.

So:

• bladene = the leaves
• not usually a separate word + noun in this kind of basic sentence

This is one of the biggest differences from English. In Norwegian, the noun often carries the meaning of the by itself.

Yes. Spiser is the present tense of å spise (to eat).

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

In this sentence:

• Skadedyret spiser bladene = The pest eats the leaves

Norwegian present tense is often used where English might use either eats or is eating, depending on the situation.

Because Norwegian verbs do not change according to the subject in the present tense.

For example:

• jeg spiser = I eat
• du spiser = you eat
• han spiser = he eats
• vi spiser = we eat

The verb stays spiser for all persons.

That is much simpler than English, where only some forms change, like he eats.

This sentence uses the basic Norwegian word order:

• Subject + Verb + Object

So:

• Skadedyret = subject
• spiser = verb
• bladene = object

That is the same basic order as in English:

• The pest eats the leaves

So this sentence is very straightforward.

Skadedyr is neuter.

You can tell from the indefinite article:

• et skadedyr = a pest

And in the definite singular, neuter nouns often take -et:

• skadedyret = the pest

A useful rule here is that compound nouns usually take the gender of the final element. Since dyr is neuter, skadedyr is neuter too.

It can be a little tricky, because blad is one of those nouns where the singular and indefinite plural can look the same.

Typical forms are:

• et blad = a leaf
• blad = leaves
• bladene = the leaves

So blad can function as the plural leaves in many contexts.

In this sentence, though, you have bladene, which clearly means the leaves.

Yes. Blad can have several meanings depending on context, such as:

• leaf of a plant
• sheet
• page
• blade
• sometimes part of the name of a newspaper or magazine

But in Skadedyret spiser bladene, the natural meaning is clearly leaves, because something described as a pest would commonly eat plant leaves.

A learner-friendly approximation is:

• Skadedyret spiser bladene
• roughly: SKAH-deh-dy-ret SPEE-ser BLAH-deh-neh

A few helpful notes:

• skade begins with ska-, not like English shade
• dyr has a vowel sound that does not exist in English; it is one of the harder Norwegian vowels
• spiser has a clear s sound
• bladene has three syllables: bla-de-ne

If you want, you can think of the stress roughly like this:

• SKAdedyret
• SPIser
• BLAdene

Yes, depending on what you want to emphasize.

For example:

• Et skadedyr spiser bladene. = A pest is eating the leaves / A pest eats the leaves
• Skadedyret spiser et blad. = The pest eats a leaf
• Bladene spises av skadedyret. = The leaves are eaten by the pest (more formal/passive)

But Skadedyret spiser bladene is the most direct and natural way to say The pest eats the leaves.