Learn Hardcore Norwegian: Ungdom fra byen samles på gresset for å se på regnbuen. - Youth from the city gather on the grass to watch the rainbow.

In Norwegian, ungdom can function as a collective or mass noun meaning “youth” in general. It doesn’t need an indefinite article or a plural ending when you’re talking about young people as a group. If you wanted to emphasize individual young persons, you could use ungdommer (plural) or ungdommene (definite plural “the youths”), but here Ungdom refers to youth collectively, so it stands alone.

What does fra do in fra byen, and why is byen in the definite form?

fra means “from.”
When you say “from the city” in a general sense, you use fra
- definite noun: byen (“the city”).
If you meant “from a city” (any city), you would say fra en by. Here it’s clear they come from their hometown, so fra byen is natural.

What kind of verb is samles, and how does it differ from samler?

samles is the present tense of the es-passive (autopassive) form of å samle.
It means “gather” or “come together” intransitively (“are gathering”).
samler is the active form (“(they) gather something”), so if you used samler seg, you’d need the reflexive pronoun seg:
• Ungdom fra byen samler seg på gresset…
Both mean “young people gather on the grass…,” but samles is more concise.

Why is the phrase på gresset used, and why is gresset definite?

på is the preposition “on.”
gress (“grass”) is a neuter noun, so its definite form is gresset (grass + -et).
Saying på gresset = “on the grass,” equivalent to English “on the grass,” not just “on grass.”

Why do we use for å se på instead of just å se på?

for å introduces purpose: “in order to.”
å se på alone could mark an infinitive, but without for it doesn’t clearly express “they gather for the purpose of looking at.”
for å se på regnbuen = “in order to look at the rainbow.”

Why is the verb and preposition split in se på regnbuen?

se = “to see,” se på = “to look at.”
The preposition på is mandatory when you direct your gaze toward something.
Without på, se regnbuen would sound odd; you always say se på noe = “look at sth.”

Why are gresset and regnbuen in their definite forms?

Norwegian attaches the definite article as a suffix:

Neuter nouns get -et → gress → gresset (“the grass”)
Common-gender nouns get -en → regnbue → regnbuen (“the rainbow”)
Here both are definite because they refer to specific, context-known items—the grass they stand on and the rainbow they’re watching.

Could we move for å se på regnbuen to the front of the sentence?

Yes, but you must keep the verb in second position:

Original: Ungdom fra byen samles på gresset for å se på regnbuen.
Fronted purpose: For å se på regnbuen samles ungdom fra byen på gresset.
It’s grammatical, though the original order is more common in spoken and written Norwegian.