Extraposition and Heavy-NP/Clause Shift | Icelandic Grammar

Icelandic, like English, prefers to keep its sentences front-light and back-heavy: short, easily-processed material early, long and complicated material late. The grammar enforces this preference with two rightward movements — extraposition, which sends a whole clause to the end and parks the expletive það in the slot it vacated, and heavy-NP shift, which slides a long noun phrase rightward past lighter words. Both exist because a clause-sized or phrase-sized lump is hard to hold in mind at the front of a sentence while you wait for the verb. This page is about those two movements and, above all, about the unifying fact that the það of Það er gaman að ferðast ("It is fun to travel") is not a special idiom but the very same placeholder you already know from existentials. (For the inventory of það's jobs see syntax/dummy-thad; for the existential construction proper, syntax/existential-sentences. This page assumes those and focuses on the rightward shifts themselves.)

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One mechanism runs through this whole page: a heavy constituent — a clause, or a long phrase — does not sit comfortably at the front, so Icelandic moves it to the end. When that constituent was the subject, the now-empty subject slot is filled by the expletive það. Extraposition and heavy shift are two faces of the same back-loading principle.

Extraposition of a clausal subject: það holds the slot

Start with the core case. A finite clause or an infinitival að-clause can serve as the subject of a sentence — að ferðast ("to travel"), að hann skyldi koma ("that he should come"). In principle such a clause could sit in the subject position at the front: Að ferðast er gaman ("To travel is fun"). Icelandic allows this, but it is stiff and marked — a clause-sized subject in first position makes the reader hold a whole proposition open before reaching the verb. The natural, default solution is to extrapose the clause to the end and fill the vacated subject slot with the expletive það.

Það er gaman að ferðast.

It is fun to travel. — the real subject is the infinitival clause að ferðast, extraposed to the end; það is a placeholder holding the subject slot, exactly as 'it' does in English.

Það er nauðsynlegt að bóka borð fyrirfram.

It is necessary to book a table in advance. — extraposed að-clause (að bóka borð fyrirfram) as the logical subject; the predicate nauðsynlegt comes first with það propping up the front.

Það kom mér á óvart að hann skyldi koma.

It surprised me that he should come. — a finite að-clause extraposed; það fills the subject slot, the experiencer mér sits in the middle, and the heavy clause lands at the end.

The logic is identical to English it is fun to travel / it surprised me that he came: the pronoun is a grammatical stand-in, not a referring word. The difference is that Icelandic's expletive is það — the same word that means "that/it" and the same word that opens existentials (Það er köttur í garðinum "There is a cat in the garden"). That coincidence is not an accident; it is the point.

Why það is one system, not three

Competitors and textbooks routinely list það's uses as if they were unrelated entries in a phrasebook: "það = it," "það = there (existential)," "það = dummy weather subject," "það = placeholder for a clause." The deeper and more useful truth is that these collapse into one expletive system. Icelandic main clauses obey the verb-second rule, which means something must occupy the clause-initial position before the finite verb. When the logical subject is missing from that slot — because it is unexpressed (weather), postponed (existential), or extraposed (a clause) — það steps in to satisfy V2. Look at the parallel:

Construction	Example	What það is doing
Weather/ambient	Það rignir. "It is raining."	fills the subject slot; no logical subject at all
Existential	Það er köttur í garðinum. "There is a cat in the garden."	fills the slot; the notional subject köttur sits later
Clausal-subject extraposition	Það er gaman að ferðast. "It is fun to travel."	fills the slot; the real subject (the clause) is extraposed to the end

In all three, það is the same grammatical filler, demanded by the same V2 requirement, vacated by the same kind of "the real subject is not here" situation. Recognising this means you stop memorising Það er gaman að… as a frozen idiom and start generating it: any predicate that takes a clausal subject (gaman, leiðinlegt, nauðsynlegt, gott, ómögulegt, ljóst, augljóst…) slots straight into Það er ADJ að….

Það er leiðinlegt að þurfa að segja þetta, en við töpuðum.

It is unpleasant to have to say this, but we lost. — productive frame: Það er + adjective + extraposed að-clause. The same skeleton as 'It is fun to travel'.

Það er ljóst að við náum ekki vélinni.

It is clear that we won't catch the plane. — extraposed finite clause (að við náum ekki vélinni); the same expletive það as in the existential and weather constructions.

það disappears when the slot is already filled

Here is the cleanest proof that það is a slot-filler rather than a meaningful word: it vanishes the moment something else occupies the clause-initial position. Because það exists only to satisfy V2, fronting any other constituent — an adverbial, the experiencer — makes the expletive unnecessary, and it is dropped.

Í raun er gaman að ferðast.

Really, it is fun to travel. — the adverbial Í raun now fills the first slot, V2 is satisfied without það, so the expletive is gone (not *Í raun það er gaman).

Mér kom á óvart að hann skyldi koma.

It surprised me that he should come. — the experiencer Mér is fronted into the first slot; no það is needed. Compare Það kom mér á óvart að…, where það fills the slot only because nothing else does.

This alternation — það present at the front, það absent when something is fronted — is exactly the behaviour of the existential and weather það, and it confirms they are one and the same device. The expletive is a placeholder of last resort, never a contentful subject.

Extraposition of a clausal complement (object)

Clauses do not only function as subjects; they also function as objects/complements of verbs and adjectives. A clausal complement likewise prefers the end of the sentence, and when its host already has its own subject, no expletive is needed — the clause simply trails the verb. The "extraposition" here is just the natural late placement of the heavy clause.

Hún sagði mér að hún kæmist ekki á fundinn.

She told me that she couldn't make the meeting. — the að-clause is the complement of sagði; it lands at the end, after the lighter object mér, where heavy material belongs.

Ég lofa þér því að við klárum þetta fyrir helgi.

I promise you that we'll finish this before the weekend. — the cataphoric því points forward to the extraposed clause að við klárum…; the heavy clause sits last.

That second example shows a refinement worth flagging: some verbs (and especially verb+preposition frames) take a cataphoric pronoun — því, þess, það — that points forward to the extraposed clause. Ég lofa þér *því að… literally pre-announces the clause with því ("it/that," dative governed by *lofa), then delivers the clause itself at the end. This is the object-side echo of subject það: a light pronoun holds the grammatical relation while the heavy clause is deferred.

Heavy-NP shift: sliding a long object rightward

The second rightward movement is heavy-NP shift. Icelandic, like English, normally keeps a direct object close to its verb. But when that object is unusually long and heavy — a noun with a string of modifiers, a relative clause, a coordinated list — it can slide rightward, past lighter material (an adverbial, a particle, a second object), so that the bulky phrase comes last. The motivation is processing: you don't want a heavy lump wedged between the verb and a short element that the verb also needs.

Compare a light object (which stays put) with a heavy one (which shifts):

Ég setti bókina á borðið.

I put the book on the table. — light object bókina stays right after the verb, before the adverbial á borðið.

Ég setti á borðið allar bækurnar sem ég hafði fengið lánaðar á bókasafninu.

I put on the table all the books that I had borrowed from the library. — heavy object (allar bækurnar sem… bókasafninu) is shifted rightward past the short adverbial á borðið, so the long phrase lands last.

Keeping the heavy noun phrase in its base position — Ég setti allar bækurnar sem ég hafði fengið lánaðar á bókasafninu á borðið — is grammatical but front-heavy and harder to parse: the listener must hold the verb's destination (á borðið) in suspense through a long relative clause. Shifting the heavy NP to the end resolves that. The same effect appears with particle verbs and with double objects, where the short element clings to the verb and the long one is exiled to the right.

Hún gaf okkur öllum þennan dýrindis konfektkassa sem hún hafði keypt í útlöndum.

She gave us all this exquisite box of chocolates that she had bought abroad. — the short indirect object okkur öllum stays close to the verb; the heavy direct object (þennan… útlöndum) is shifted to the end.

Þau hentu út öllum gömlu blöðunum sem höfðu safnast upp í kjallaranum.

They threw out all the old newspapers that had piled up in the basement. — the particle út stays with the verb; the heavy object follows it, shifted right.

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Heavy-NP shift is a tendency, not an iron rule — the heavier the phrase and the lighter the material it jumps over, the stronger the pull to shift. A bare noun never shifts; a noun trailing a long relative clause almost always reads better shifted to the end. When in doubt, ask which version makes the listener wait less.

English vs Icelandic: same instinct, one extra obligation

For an English speaker the back-loading instinct is already native: you say It is fun to travel, not To travel is fun, in ordinary speech, and you say I gave the children everything they had asked for rather than wedging the long object before the children. So extraposition and heavy shift will feel intuitive. The one genuinely new obligation is the placeholder. English uses it to fill the subject slot of an extraposed clause, and so does Icelandic with það — but English also tolerates a bare existential there and several semi-fixed dummies, while Icelandic routes all of these through the single expletive það governed by V2. The practical upshot: when a clause is your logical subject and nothing else fronts, you must supply það. Leaving the slot empty (*"Is fun to travel") is as ungrammatical in Icelandic as in English, and leaving a heavy clause sitting in first position is merely awkward, not wrong.

Common Mistakes

❌ Er gaman að ferðast.

Missing the placeholder — with nothing fronted, the subject slot must be filled. Icelandic needs the expletive: Það er gaman að ferðast.

✅ Það er gaman að ferðast.

It is fun to travel. — það holds the subject slot for the extraposed clause.

When a clause is the logical subject and no other constituent is fronted, you must supply það. This is the same requirement as the existential and weather það: V2 demands a filler for the empty subject slot.

❌ Að hann skyldi koma kom mér á óvart, og líka að hann væri einn.

Front-heavy — leaving a long clausal subject in first position is stiff and hard to parse, especially when a second clause piles on.

✅ Það kom mér á óvart að hann skyldi koma, og líka að hann væri einn.

It surprised me that he should come, and also that he was alone. — extrapose the heavy clause(s) to the end; það props up the front.

A clause-sized subject parked at the front forces the reader to hold an entire proposition open before the verb. Extrapose it and let það hold the slot — the default, natural order.

❌ Í raun það er gaman að ferðast.

Doubled filler — once Í raun is fronted, V2 is already satisfied, so það must drop: Í raun er gaman að ferðast.

✅ Í raun er gaman að ferðast.

Really, it is fun to travel. — the fronted adverbial fills slot one; no expletive það.

This is the tell that það is a slot-filler, not a meaningful subject: front anything else and the expletive disappears. Keeping both is the error of treating Það er gaman as a frozen unit.

❌ Ég setti allar bækurnar sem ég hafði fengið lánaðar á bókasafninu á borðið.

Front-heavy object — the long NP is wedged before the short adverbial á borðið, making the listener wait through a relative clause for the destination.

✅ Ég setti á borðið allar bækurnar sem ég hafði fengið lánaðar á bókasafninu.

I put on the table all the books I'd borrowed from the library. — heavy-NP shift sends the bulky object to the end, past the short adverbial.

Not strictly ungrammatical, but markedly worse processing. When the object is heavy and the following material is light, shift the heavy phrase rightward.

Key Takeaways

Icelandic back-loads: heavy material — a clause, or a long phrase — moves to the end of the sentence.
Extraposition sends a clausal subject to the end and fills the vacated subject slot with the expletive það (Það er gaman að ferðast, Það kom mér á óvart að hann skyldi koma).
That það is the same expletive as the existential and weather það — one V2-driven slot-filler, not three idioms. It disappears the moment another constituent is fronted (Í raun er gaman að…).
Clausal complements likewise sit at the end; some verbs pre-announce them with a cataphoric því/þess (Ég lofa þér því að…).
Heavy-NP shift slides a long, heavy object rightward past lighter material for easier processing — a tendency that strengthens with the weight of the phrase.
For English speakers the instinct is familiar; the one new obligation is supplying the placeholder það when a clause is the logical subject and nothing else fronts.

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