Barnið heldur á bangsanum sínum.

Because halda á is a common Icelandic expression meaning to hold something in your hands / be holding something.

By itself, halda often means things like:

• keep
• maintain
• believe / think
• hold in other, less physical senses

So in this sentence, heldur á tells you this is the physical action of holding the teddy bear.

Not really, at least not in a word-for-word way.

Á often does mean on, but with some verbs Icelandic uses fixed verb + preposition combinations. Halda á is one of them. So it is best learned as a unit:

• halda á e-u = hold something

Also, in this expression, á controls the dative case, which is why the next noun is not in its basic form.

Because á in halda á takes the dative, and bangsanum is the dative singular definite form.

So:

• dictionary form: bangsi = teddy bear
• here: bangsanum = the teddy bear in the dative singular

The ending -num is a very common sign of dative singular definite in Icelandic.

The dictionary form is bangsi.

It is a masculine noun. In this sentence it changes form because it is:

• singular
• definite
• dative

That gives bangsanum.

Because sinn is the reflexive possessive pronoun.

Icelandic uses sinn when the possessor is the same as the subject of the sentence. So here:

• subject: barnið = the child
• possessed thing: bangsanum sínum = its own teddy bear

So the meaning is specifically the child is holding its own teddy bear.

If the teddy bear belonged to someone else, Icelandic would use a non-reflexive possessive, such as:

• hans = his
• hennar = her
• þess = its

Because sinn agrees with the noun being possessed, not with the owner.

Here, the possessed noun is bangsanum, which is:

• masculine
• singular
• dative

So the possessive must match that, giving sínum.

This is important: even though barnið is neuter, the form is still sínum, because it matches bangsanum, not barnið.

Barnið comes from barn = child.

The ending -ið is the suffixed definite article, so:

• barn = a child / child
• barnið = the child

Also, barn is a neuter noun. In this sentence, barnið is the subject.

The base form is halda.

In this sentence, heldur is:

• present tense
• 3rd person singular

So it means holds / is holding.

This is a good example of how Icelandic verbs often change their stem when conjugated, so halda becomes heldur, not haldur.

Not always.

In English, his, her, or their can sometimes already imply that the possessor is the subject. Icelandic is stricter about this distinction, so it often uses sinn where English may or may not use own.

So depending on context, bangsanum sínum could be translated as:

• his own teddy bear
• her own teddy bear
• its own teddy bear
• sometimes just his/her teddy bear

But grammatically, Icelandic is clearly marking it as belonging to the subject.

This is a very normal, neutral Icelandic word order:

• Barnið = subject
• heldur = verb
• á bangsanum sínum = prepositional phrase

So the sentence structure is basically:

Subject + Verb + Prepositional phrase

The part á bangsanum sínum stays together because á belongs with the expression halda á.