Á fimmtudag fer hún með börnin á leikvöllinn bakvið húsið.

Á fimmtudag means on Thursday.

In Icelandic, days of the week are often used with á to mean on a particular day. In this expression, fimmtudag is the accusative singular of fimmtudagur.

So:

• fimmtudagur = Thursday
• á fimmtudag = on Thursday

English speakers often look for an article here, but Icelandic normally does not say on the Thursday in this kind of general time expression.

This is because Icelandic follows a verb-second pattern in main clauses.

The first element in the sentence is Á fimmtudag. Once that time phrase takes first position, the finite verb usually comes next:

• Á fimmtudag fer hún ...

If you started with the subject instead, you would get:

• Hún fer á fimmtudag ...

Both are normal. The first version gives a little more emphasis to Thursday.

The dictionary form is fara, meaning to go.

Fer is the 3rd person singular present tense form:

• ég fer = I go
• þú ferð = you go
• hún fer = she goes

So here fer hún means she goes or, depending on context, she is going / will go.

In this sentence, it is closer to takes.

That is because fara together with með can form an expression meaning go with / take along / take someone somewhere.

So:

• Hún fer með börnin á leikvöllinn
  = She takes the children to the playground

Even though the basic verb fara means go, the combination here gives a more English-like sense of take.

Börnin means the children.

The base noun is:

• barn = child

Its plural is:

• börn = children

And the definite plural is:

• börnin = the children

A very important Icelandic feature is that the definite article is usually attached to the end of the noun instead of being a separate word. So Icelandic often says:

• börnin = the children
• not a separate word like English the children

This is a very good question, because með often makes learners expect a dative form like börnunum.

Here, though, fer með börnin is best understood as a verbal expression meaning takes the children / goes with the children in a taking-along sense.

So börnin functions as the object of the whole idea, not just as the object of a simple preposition meaning with.

Compare:

• Hún fer með börnin á leikvöllinn
  = she takes the children to the playground

but

• Hún fer á leikvöllinn með börnunum
  = she goes to the playground with the children

In the second sentence, með has the ordinary meaning with, and börnunum is dative.

Because this sentence expresses movement toward a place.

With á, Icelandic often distinguishes between:

• accusative for movement to a place
• dative for location at/on a place

So:

• á leikvöllinn = to the playground
• á leikvellinum = at/on the playground

Since the children are being taken to the playground, the accusative form leikvöllinn is used.

Because two things are happening at once:

1. the noun is in the accusative singular
2. it is definite: the playground

The basic nominative form is:

• leikvöllur = playground

But in this sentence, after á with motion, we need the accusative, and the noun is definite:

• leikvöllinn = the playground

A useful comparison:

• leikvöllur = a playground
• leikvöllurinn = the playground (subject form / nominative)
• leikvöllinn = the playground (object/destination form / accusative)

So the word looks quite different because Icelandic marks both case and definiteness.

Yes, it means behind.

Many learners will encounter the expression written as bak við, and that is a very common way to see it. In your sentence, it appears as bakvið, which represents the same meaning.

So:

• bakvið húsið
• bak við húsið

both mean:

• behind the house

If you use teaching materials or dictionaries, you may often find bak við listed.

Húsið means the house.

The base noun is:

• hús = house

With the suffixed definite article:

• húsið = the house

Again, Icelandic usually puts the at the end of the noun instead of using a separate word.

Also, because hús is a neuter noun, some case forms look the same. So in a phrase like bakvið húsið, you do not see an obvious English-style case change in the form itself.

It can mean either, depending on context.

Icelandic present tense often covers several things that English may separate:

• a habitual action: On Thursdays she takes the children...
• a planned future action: On Thursday she is taking the children... / will take the children...

So without extra context, Á fimmtudag fer hún með börnin ... can be understood in more than one way. The surrounding conversation usually makes it clear whether it is a routine or a one-time plan.