slå ("to hit, strike, beat") is a workhorse you will use far beyond its literal sense. It is the everyday verb for switching things on (slå på lyset), for looking things up (slå opp i ordboka), for things striking you mentally (det slår meg), and for a dozen other idioms. It is also a short å-stem strong verb, which means its forms are compact but irregular — well worth memorising early.
Conjugation
Class: strong, å-stem (contracted). Auxiliary: ha.
| Tense / mood | Norwegian | English |
|---|---|---|
| Infinitiv | å slå | to hit / to strike |
| Presens | slår | hit(s), strike(s) |
| Preteritum | slo | hit, struck |
| Perfektum | har slått | have/has hit |
| Pluskvamperfektum | hadde slått | had hit |
| Futurum | skal/vil slå | will hit |
| Imperativ | slå! | hit! |
| Presens partisipp | slående | striking (adjective) |
| Passiv (infinitiv) | å slås | to be hit / to fight |
A contracted strong å-stem
slå belongs to a small club of verbs whose infinitive ends in a stressed å with no following consonant — slå, gå, stå, få, nå. They all behave irregularly, and slå runs the pattern å → o → å: slå / slo / slått. The preterite slo is simply the bare vowel o with no ending, which feels strange to English speakers used to a -ed or at least a consonant; trust it.
The English cognate is slay / slew / slain — and the kinship is real: both descend from the same Germanic strong verb, and you can hear the vowel shift (slå/slo ↔ slay/slew) echo across the two languages. But beware the meaning drift: Norwegian slå is everyday "hit/strike," not the dramatic "slay." Use it freely; it carries no violence on its own.
Han slo neven i bordet og reiste seg.
He banged his fist on the table and stood up.
Klokka slo tolv akkurat da vi kom inn.
The clock struck twelve just as we came in.
Jeg har aldri slått noen i hele mitt liv.
I've never hit anyone in my entire life.
slå på vs slå av — turning things on and off
This is the highest-frequency everyday use. slå på = switch on; slå av = switch off. Norwegian uses slå ("strike") where English uses "turn" — a small but constant difference. The particle (på / av) is stressed and carries the meaning, and the object usually slots between verb and particle when it's a pronoun (slå den på) or after the particle when it's a full noun (slå på lyset).
Kan du slå på lyset? Det er helt mørkt her inne.
Can you turn on the light? It's completely dark in here.
Husk å slå av komfyren før du går.
Remember to turn off the stove before you leave.
PC-en slo seg av midt i presentasjonen.
The computer switched itself off in the middle of the presentation.
More essential idioms
A cluster of fixed expressions are worth learning whole, because none is fully literal:
- slå opp — (1) to look up, in a book or online: slå opp i ordboka; (2) to break up, of a couple: de slo opp; (3) to put up / set up: slå opp et telt.
- slå seg — to hurt oneself (by hitting): Jeg slo meg på kneet. The reflexive seg is essential; without it the verb means hitting someone else.
- slå sammen — to merge, combine, fold together: slå sammen to selskaper.
- det slår meg — it strikes me / it occurs to me. A fixed mental idiom, just like English "it strikes me that…".
Hvis du ikke kan ordet, slå det opp.
If you don't know the word, look it up.
Jeg falt på isen og slo meg ganske stygt.
I fell on the ice and hurt myself pretty badly.
Det slår meg at vi har glemt å invitere Mari.
It strikes me that we've forgotten to invite Mari.
Common Mistakes
❌ Han slådde døra igjen.
Incorrect — slå is strong; the preterite is slo, never a weak -dde form
✅ Han slo døra igjen.
He slammed the door shut.
❌ Jeg har slo av varmen.
Incorrect — slo is the preterite; after har use the supine slått
✅ Jeg har slått av varmen.
I've turned off the heat.
❌ Vennligst skru på lyset for meg.
Understandable, but the idiomatic verb for a switch is slå, not skru (skru = screw/twist)
✅ Vennligst slå på lyset for meg.
Please turn on the light for me.
❌ Jeg slo på kneet da jeg falt.
Incorrect — to hurt yourself you need the reflexive: slå seg
✅ Jeg slo meg på kneet da jeg falt.
I hurt my knee when I fell.
Key Takeaways
- slå / slår / slo / har slått / slå! — a contracted strong å-stem (å → o → å), cousin of English slay/slew.
- Norwegian uses slå where English uses "turn": slå på = turn on, slå av = turn off.
- Learn the idioms whole: slå opp (look up / break up), slå seg (hurt oneself), slå sammen (merge), det slår meg (it strikes me).
- Spelling traps: preterite slo (no ending), supine slått (å + double t).
Now practice Norwegian
Reading grammar gets you part of the way. The exercises are where it sticks — free, no signup needed.
Start learning Norwegian→Related Topics
- The Strong Verb Ablaut ClassesB1 — The ablaut (vowel-change) classes of Norwegian strong verbs grouped by pattern — i–a–u, i–e–e, y/ju–ø–ø, a–o–å, e–a–e — each mapped onto its English cognate class so you can often guess the forms.
- Strong Verbs: Ablaut and the Vowel-Change ClassesA2 — Strong verbs build the past by changing the stem vowel instead of adding an ending (drikke → drakk → drukket) — the main ablaut series, grouped, with full tables and English cognate hooks.
- Verb Reference: How to Use These TablesA2 — How to read the Norwegian verb-reference pages — the five principal parts, weak vs strong classes, and the supine (the har-form).