synda ("to swim") is a high-frequency verb in a country where the public pool is a national institution — but it conceals two small traps that catch learners. First, the stem is spelled with y, not i, even though the two sound identical in modern Icelandic — a pure spelling pitfall. Second, and more interesting grammatically, the consonant cluster nd hardens to nt in the past tense: synda → synti. That voiceless -ti (rather than the -di you might expect) is the one thing about this verb worth circling. It is a weak i-verb, intransitive, and — because its stem vowel is y, not a short a — it shows no u-umlaut anywhere.
Conjugation
Class: weak, i-verb (the -ti preterite after nd). Auxiliary: hafa — ég hef synt "I have swum."
| Principal parts | |
|---|---|
| Infinitive | að synda |
| 3sg present | syndir |
| 3sg past | synti |
| Supine | synt |
| Person | Present (nútíð) | Past (þátíð) |
|---|---|---|
| ég | syndi | synti |
| þú | syndir | syntir |
| hann / hún / það | syndir | synti |
| við | syndum | syntum |
| þið | syndið | syntuð |
| þeir / þær / þau | synda | syntu |
| Person | Present subjunctive | Past subjunctive |
|---|---|---|
| ég | syndi | synti |
| þú | syndir | syntir |
| hann / hún / það | syndi | synti |
| við | syndum | syntum |
| þið | syndið | syntuð |
| þeir / þær / þau | syndi | syntu |
| Non-finite & imperative | |
|---|---|
| Imperative (þú) | syntu! (bare form: synd!) |
| Imperative (þið) | syndið! |
| Supine | synt |
| Past participle (m/f/n) | syntur / synt / synt |
The y spelling-trap
In modern Icelandic, y and i are pronounced exactly the same (and ý the same as í). That makes synda a spelling minefield: your ear gives you no clue whether to write synda or "sinda." It is y. The same goes for the noun sund ("swimming / a swim / the pool") and the everyday phrase fara í sund "to go swimming / to the pool" — all with y-less sund, but the verb with y. Memorise the spelling visually, because pronunciation will not save you.
Ég syndi á hverjum morgni fyrir vinnu.
I swim every morning before work.
Hún synti tvo kílómetra í gær.
She swam two kilometres yesterday.
Eigum við að fara í sund eftir skóla?
Shall we go to the pool after school?
kunna að synda vs. geta synt — skill vs. circumstance
Icelandic, like English, draws a fine line between knowing how to swim and being able to swim right now. Use kunna að synda for the learned skill ("I know how to swim"), and geta synt (with the supine synt) for the circumstance ("I'm able to swim", e.g. the water's calm enough, I'm not injured).
Sonur minn er fjögurra ára og kann nú þegar að synda.
My son is four and already knows how to swim.
Ég kann að synda, en ég gat ekki synt í þessum öldum.
I know how to swim, but I couldn't swim in those waves.
Note how the two constructions differ in form: kunna + the infinitive að synda, but geta + the bare supine synt (no að). That contrast in complement form is a reliable tell of which verb you've chosen.
Intransitive — and how to add a direction
synda is intransitive: it takes no direct object. To say where someone swims to, add a directional phrase, not an accusative object.
Strákarnir syntu út að baujunni og til baka.
The boys swam out to the buoy and back.
Syntu varlega, það er straumur hérna.
Swim carefully, there's a current here.
Common Mistakes
❌ Hún syndi yfir vatnið í gær.
Incorrect — that's the present form; the past hardens nd to nt: synti
✅ Hún synti yfir vatnið í gær.
She swam across the lake yesterday.
❌ Ég sindi í sjónum á sumrin.
Incorrect spelling — the stem is written with y, not i: syndi
✅ Ég syndi í sjónum á sumrin.
I swim in the sea in the summer.
❌ Ég get synda mjög hratt.
Incorrect — geta takes the supine synt, not the infinitive synda
✅ Ég get synt mjög hratt.
I can swim very fast.
❌ Ég hef syndað tíu sinnum í þessari viku.
Incorrect — synda is not an -aði verb; the supine is synt
✅ Ég hef synt tíu sinnum í þessari viku.
I've swum ten times this week.
Key Takeaways
- synda / syndir / synti / synt — a weak i-verb; the past hardens the cluster nd → nt (synti, supine synt), giving a voiceless -ti, not -di.
- Spelling: the stem is y (synda), even though y and i sound identical. Don't trust your ear.
- No u-umlaut: the y stem vowel is immune — við syndum, not "söndum."
- kunna að synda (+ infinitive) = "know how to swim" (skill); geta synt (+ supine) = "be able to swim" (circumstance).
- Intransitive: no direct object; show direction with a phrase (synda út að baujunni). Auxiliary is hafa: ég hef synt.
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Start learning Icelandic→Related Topics
- The Weak Preterite: -aði, -di, -ði, -tiA2 — How to choose and form the weak past tense — Class-1 -a verbs take -aði (tala → talaði, plural töluðum), Class-2 verbs take the short dental -di/-ði/-ti picked by the preceding sound (reyndi, dæmdi, keypti) — with the full tala paradigm and the 'when in doubt, -aði' default for unknown verbs.