Brauðið varð hart.

Brauðið means the bread, while brauð means just bread.

In Icelandic, the definite article the is usually added to the end of the noun instead of written as a separate word.

• brauð = bread
• brauðið = the bread

So the -ið here is the suffixed definite article for a neuter singular noun.

The dictionary form is brauð.

That is the basic indefinite singular form, the one you would usually find in a dictionary.
Brauðið is just the definite form built from it.

• brauð = bread
• brauðið = the bread

Also, brauð is a neuter noun.

Varð is the past tense of verða, which usually means to become, to get, or to turn.

So:

• verða = to become
• varð = became

In this sentence, Brauðið varð hart means that the bread changed state: it became hard.

This is a very important distinction:

• var = was (from vera, to be)
• varð = became (from verða, to become)

So:

• Brauðið var hart = The bread was hard
• Brauðið varð hart = The bread became hard

The second sentence emphasizes a change. The bread was not hard before, but then it became hard.

Because hart is the neuter singular form of the adjective harður (hard).

Icelandic adjectives must agree with the noun they describe in gender, number, and often case.

Since brauð is:

• neuter
• singular

the adjective must also be neuter singular:

• harður = masculine singular
• hörð = feminine singular
• hart = neuter singular

So brauðið varð hart is correct because brauðið is neuter singular.

It is a predicate adjective.

That means it is not placed directly before the noun like hard bread. Instead, it comes after the verb and describes the subject.

Compare:

• hart brauð = hard bread
  
  • here the adjective directly modifies the noun
• Brauðið varð hart = The bread became hard
  
  • here hart is linked to the subject through the verb varð

This works much like English The bread became hard.

Brauðið is in the nominative case because it is the subject of the sentence.

The adjective hart is also understood as nominative, because with verbs like vera (to be) and verða (to become), the predicate adjective normally agrees with the subject.

So the structure is basically:

• subject in nominative
• verb
• predicate adjective agreeing with the subject

Yes, often you can.

So Brauðið varð hart can be understood as:

• The bread became hard
• The bread got hard

Both are natural English translations.
Became is a bit more neutral and literal, while got is more conversational.

Yes, but Brauðið varð hart is the normal, neutral word order.

It follows the standard pattern:

• subject
  • verb
    • predicate adjective

You may sometimes see different word orders in Icelandic for emphasis or in more complex sentences, but for a simple statement like this, Brauðið varð hart is the most natural form.

A good set of forms to memorize would be:

• brauð = bread
• brauðið = the bread
• verða = to become
• varð = became
• harður = hard
• hart = hard, neuter singular form

This sentence is useful because it shows three very common Icelandic patterns at once:

1. the definite article attached to the noun
2. a past tense verb
3. adjective agreement with a neuter subject