Learn Hardcore Dutch: In onze straat is het zelden zo stil. - In our street it is rarely this quiet.

Dutch main clauses are verb-second (V2). Whatever you put first—here the adverbial phrase In onze straat—takes position 1, and the finite verb (is) must be position 2. The subject (het) follows the verb: In onze straat | is | het ...
Without fronting, you’d get the neutral order: Het is ... in onze straat.

What does het refer to here?

It’s a dummy/expletive het, like English “it” in “It is quiet.” It doesn’t refer to straat; it refers to the general situation/ambient conditions.

Can I also say Het is zelden zo stil in onze straat?

Yes. Both are natural.

In onze straat is het ... sets the location as the topic/focus.
Het is ... in onze straat is the neutral/default order.
Meaning is the same; the difference is emphasis.

Is Zelden is het zo stil in onze straat correct?

Yes. Fronting Zelden (rarely) is grammatical and adds strong emphasis or a stylistic/expressive tone. It’s more written or rhetorical than conversational.

Why in onze straat and not op or aan?

In onze straat: standard for “on our street/along our street” (where we live).
Op straat: “out on the street” (in public space, no specific street: e.g., De kinderen spelen op straat).
Op onze straat: nonstandard in most of the Netherlands; may occur regionally, but avoid in standard Dutch.
Aan de straat: used for things located along/facing the street (e.g., Het huis ligt aan de straat).

What does zo add to stil?

Zo intensifies degree: zo stil = “so/this quiet.” The sentence says it’s rare to be as quiet as the current/reference situation, not just “quiet” in general.

Can I say Het is zo zelden stil in onze straat?

Yes, but the meaning shifts:

Het is zelden zo stil = It’s rarely this quiet (emphasis on degree).
Het is zo zelden stil = It is so rarely quiet (emphasis on frequency).
Both are correct; choose based on what you want to stress.

What’s the difference between stil, rustig, and kalm?

Stil: quiet/silent (few or no sounds).
Rustig: calm/peaceful (low activity, not hectic; may still have some sound).
Kalm: calm/tranquil (often about mood/atmosphere).
You could say In onze straat is het zelden zo rustig, but that subtly shifts the meaning from silence to calmness/low traffic.

Why doesn’t stil take an -e here?

After linking verbs like zijn/worden/blijven, adjectives are predicative and uninflected: het is stil.
Attributive adjectives (before a noun) take -e in most cases: een stille straat.

Is zelden the same as zeldzaam?

No.

Zelden = adverb “rarely/seldom” (modifies verbs/adjectives): Het is zelden zo stil.
Zeldzaam = adjective “rare” (modifies nouns): een zeldzame vogel.
Also note: there’s no zeldens in standard Dutch.

Can I use er instead of het here?

Not in this structure. Er is usually introduces the existence of a noun phrase (e.g., Er is een file).

Wrong/odd here: In onze straat is er zelden zo stil.
Possible with a noun: Er is zelden zoveel stilte in onze straat.
Stick with Het is zelden zo stil for a predicate adjective.

Why onze and not ons straat?

Because straat is a common-gender (de-) noun.

de-words: de straat → onze straat
het-words (singular): het huis → ons huis

How do I put this in the past or future?

Past: In onze straat was het zelden zo stil.
Future: In onze straat zal het zelden zo stil zijn / Het zal in onze straat zelden zo stil zijn.
With a modal (zal), the finite verb is second and zijn goes to the end.

Can I use niet instead of zelden?

Different meaning:

In onze straat is het niet zo stil = It’s not that quiet (negates degree now).
In onze straat is het zelden zo stil = It’s rarely this quiet (talks about frequency).
For “almost never,” use bijna nooit: In onze straat is het bijna nooit zo stil.