Learn Hardcore Norwegian: Hvis vi reduserer avfall, blir miljøet renere og luften klarere. - If we reduce waste, the environment becomes cleaner and the air clearer.

hvis is the conditional conjunction meaning if. It introduces a hypothetical situation ("if this happens…"). You can also use om to mean if in many contexts (e.g. Om vi reduserer avfall…), but om also means about, so using hvis often avoids ambiguity. Unlike når (when, for sure events), both hvis and om express conditions that may or may not occur.

Why are the verbs reduserer and blir in the present tense, even though the effect is in the future?

In Norwegian it’s common to use the simple present for future actions when the context is clear. Here, reduserer (“reduce/s”) and blir (“become/s”) are present-tense forms but describe a general cause-and-effect including future results. If you want to make the future aspect explicit, you can add vil:
Hvis vi reduserer avfall, vil miljøet bli renere og luften klarere.

Why does blir come before miljøet in the main clause?

Norwegian main clauses follow the V2 rule: the finite verb must be in the second position. When a sentence starts with something other than the subject (here the subordinate clause Hvis vi reduserer avfall), the verb moves to slot two, placing it before the subject. That’s why you get blir miljøet instead of miljøet blir.

How do you form comparatives like renere and klarere?

Most one-syllable adjectives form the comparative by adding -ere:
ren (clean) → renere (cleaner)
klar (clear) → klarere (clearer)
The superlative adds -est (renest, klarest). Longer adjectives often use mer (more) + adjective instead.

What do the endings in miljøet and luften indicate?

They are the definite singular forms of the nouns:
miljø is neuter → definite -et → miljøet (“the environment”)
luft is common gender → definite -en → luften (“the air”)
Using the definite form here refers to those specific concepts in context.

Why is there no article before avfall?

avfall is an uncountable (mass) noun when talking about waste in general. Mass nouns in Norwegian don’t take an article when used in a generic sense, just like in English (“reduce waste”). To talk about the waste you would use the definite form avfallet.

Could I use søppel instead of avfall, and is there any nuance difference?

Yes. søppel means “rubbish/garbage” and is more colloquial—often used for household or everyday trash. avfall is more formal and covers a broader range of waste (industrial, recyclable, etc.). Both are correct; choose søppel in casual speech and avfall in formal or technical contexts.

Could I start the sentence with Når instead of Hvis?

You can say Når vi reduserer avfall…, but når means “when” in the sense of something that definitely or routinely happens (“when we reduce waste, the environment always gets cleaner”). hvis makes it conditional or hypothetical (“if we reduce waste” – it may or may not happen). Use når for a sure event and hvis for a possibility.