Hún fyllir bensíntankinn við bensíndæluna áður en við förum lengra.

No. These are two different words that just happen to look the same.

• við in við bensíndæluna is a preposition meaning at, by, or near
• við in við förum lengra is the pronoun we

So in one place it means location, and in the other it means the subject of the verb.

This is very common in Icelandic. You have to tell which við it is from the grammar around it.

Fyllir is the present tense, 3rd person singular form of the verb að fylla, meaning to fill.

Because the subject is hún meaning she, the verb has to match that:

• ég fylli = I fill
• þú fyllir = you fill
• hún fyllir = she fills

In a sentence like this, the present tense can also sound a bit like English is going to fill or fills in a planned sequence of actions.

Because bensíntankinn means the gas tank, while bensíntankur means a gas tank.

Icelandic usually adds the definite article to the end of the noun instead of using a separate word like English the.

Also, bensíntankinn is the accusative singular definite form, because it is the direct object of fyllir.

The basic pattern is:

• bensíntankur = a gas tank
• bensíntankinn = the gas tank

So the ending is doing two jobs here:

• marking definiteness
• showing the case required by the verb

Because bensíndæla is a feminine noun, and after the preposition við, it appears here in the accusative singular definite form.

So:

• bensíndæla = a gas pump
• bensíndælan = the gas pump, nominative
• bensíndæluna = the gas pump, accusative

The preposition við governs the accusative, so you get við bensíndæluna.

This is one of the big things English speakers have to get used to in Icelandic: prepositions often require a specific case.

Yes. Icelandic loves compound nouns.

Here you have:

• bensín
  • tankur = bensíntankur meaning gas tank
• bensín
  • dæla = bensíndæla meaning gas pump

The first part narrows the meaning of the second part, just like in English compounds such as school bus or coffee cup.

Then Icelandic adds its normal endings for case and definiteness:

• bensíntankinn
• bensíndæluna

So the compounds behave like ordinary nouns once they are formed.

Áður en means before when it introduces a whole clause.

So:

• áður en við förum lengra = before we go further

This is different from just learning a single word for before. In Icelandic, áður en is a very common fixed expression when a verb clause follows.

You can think of it as:

• áður = earlier / before
• en = than / when introducing this kind of clause

Together, they function as before in sentences like this.

Because förum is the conjugated verb form that matches við meaning we.

The verb is að fara meaning to go, but in a sentence you usually need a finite form, not the dictionary form.

Present tense:

• ég fer = I go
• þú ferð = you go
• hann/hún/það fer = he/she/it goes
• við förum = we go
• þið farið = you go
• þeir/þær/þau fara = they go

So við förum simply means we go.

Lengra is the comparative form used adverbially here, meaning farther or further.

It comes from the idea of long/far:

• langt = far, a long way
• lengra = farther, further

In við förum lengra, it describes the movement of going, so it works like an adverb in English:

• go farther
• go further

English speakers often expect something more literal, but Icelandic commonly uses lengra this way with verbs of movement.

The main clause is:

• Hún fyllir bensíntankinn við bensíndæluna
• subject + verb + object + place phrase

Then comes the subordinate clause:

• áður en við förum lengra

Inside that subordinate clause, the order is normal:

• við förum = we go

So the full sentence is basically:

• main action
• then the time clause telling when it happens

A useful thing to notice is that if the sentence began with the áður en clause, Icelandic would normally use main-clause verb-second order after it:

• Áður en við förum lengra fyllir hún bensíntankinn við bensíndæluna.

That word order pattern is very important in Icelandic.

Because Icelandic usually attaches the definite article to the noun itself instead of using a separate article like English the.

So:

• bensíntankinn = the gas tank
• bensíndæluna = the gas pump

This is completely normal Icelandic structure.

English:

• the gas tank
• the gas pump

Icelandic:

• gas tank + the
• gas pump + the

The article is built into the noun ending. That is why learning noun forms in Icelandic usually means learning:

• gender
• singular/plural
• case forms
• definite forms