Case Errors: Prepositions and Objects

Almost every case error an English speaker makes in Icelandic traces back to one missing question: what case does this word assign? English has so little case morphology that you never have to ask it — "with me," "to him," "from her" all use the same object form regardless of the preposition. Icelandic, by contrast, makes nearly every preposition and many verbs lexically select a case, and that selection is not negotiable. The cure is not to memorise a thousand individual facts but to build one reflex: before you put a noun or pronoun after a preposition or verb, ask which case it demands, and inflect accordingly.

This page is a catalogue. Each entry shows the wrong form, explains why it's wrong, gives the correction, and states the underlying rule. They sort into three families: prepositions, verb objects, and the motion-vs-location switch. (Quirky subjects — mér finnst, mig vantar — are a separate topic with their own page.)

Family 1: wrong case after a preposition

Every Icelandic preposition governs a case — and you can't read it off the English. með ("with") takes the dative; til ("to/of") takes the genitive; um ("about") takes the accusative. Using the bare nominative (the dictionary form), or carrying over the wrong case, is the single commonest beginner error.

Why it's wrong: með lexically selects the dative. The personal pronoun must therefore appear in its dative form, mér (not nominative ég, not accusative mig). Underlying rule: með always takes the dative — með mér, með þér, með honum, með henni, með okkur.

Why it's wrong: til ("to") is one of the few prepositions that take the genitive, and place names inflect for it just like any noun — Reykjavík → Reykjavíkur. Underlying rule: til always takes the genitive, including with proper nouns (til Akureyrar, til Íslands, til Jóns).

Why it's wrong: um ("about/around") selects the accusative, so the pronoun is mig, not ég. Underlying rule: a small group of prepositions (um, gegnum, við, fyrir in many uses) take the accusative — learn each preposition with its case.

Family 2: wrong object case with case-governing verbs

In English, every direct object looks the same: "I helped him," "I reached the bus." In Icelandic, many verbs assign a non-accusative object — most often the dative — and you have to know which. The error is using the accusative (or a bare nominative) by default.

Why it's wrong: hjálpa ("help") is a dative-governing verb: its object stands in the dative, so "you" must be þér, not the accusative þig. Underlying rule: a large class of verbs (hjálpa, bjóða, lofa, breyta, gleyma, ...) take dative objects — learn the case as part of the verb.

Why it's wrong: ná on its own (+ dative) means "reach/attain"; to "catch" or "make" a bus you need the phrasal ná í + accusative. Dropping the í changes the meaning and the structure. Underlying rule: some verbs require a preposition to take their object, and the preposition then fixes the case (ná í + accusative, hlusta á + accusative, bíða eftir + dative).

Why it's wrong: you can't attach a person as a direct object to langa this way; a wish about someone else's action is expressed with að + subjunctive. Underlying rule: when the wish is about another person acting, switch to a subordinate clause (ég vil að þú komir), not a transitive object.

Why it's wrong: gleyma ("forget") is dative-governing, so "the keys" must be lyklunum (dative plural), not accusative lyklana. Underlying rule: this is the same lexical-case principle as hjálpa — the verb, not the sentence role, picks the case.

Family 3: missing the motion-vs-location switch

A handful of prepositions — í, á, undir, yfir, fyrir, milli and others — take two cases, and the case tells you whether you mean motion toward (accusative) or being located (dative). English uses the same form for both ("into the school" / "in the school"), so learners freeze the case and get one of the two situations wrong.

Why it's wrong: fara is motion toward a goal, so í takes the accusative — í skólann. The dative skólanum would mean "located in the school," which is wrong for "going to." Underlying rule: with two-case prepositions, motion → accusative, location → dative; the verb tells you which.

Why it's wrong: vera ("to be") describes location, so í takes the dative — í skólanum. The accusative skólann would imply motion into the school, which "I am" doesn't express. Underlying rule: the same two-case rule, viewed from the static side — being somewhere is dative.

Why it's wrong: leggja ("put/lay") moves the books onto the surface, so á is accusative — á borðið. The dative borðinu describes resting position, not the act of placing. Underlying rule: even when the goal is a surface, the placing verb triggers the accusative (motion); only "the books are lying on the table" (liggja á borðinu) takes the dative.

The one habit that fixes all three families

Every error above is the same mistake wearing three costumes: the speaker chose a noun ending without first asking what the governing word demands. So build the checklist into your speech:

1. After a preposition → recall the preposition's case (með dat., til gen., um acc.). With two-case prepositions, also ask: motion (acc.) or location (dat.)?
2. After a verb → recall whether the verb assigns a non-accusative object (hjálpa, gleyma dat.) or needs a preposition (ná í, hlusta á).
3. Only then inflect the noun.

Run that loop a few hundred times and it becomes automatic — at which point the whole scattered family of "case errors" collapses into a single, manageable discipline.

Quick-reference: the words behind the errors