Heiðarleiki og þolinmæði hjálpuðu þeim að gera sambandið sterkara.

Because the subject is Heiðarleiki og þolinmæði — honesty and patience — which is a plural subject made up of two nouns joined by og (and).

So the verb has to be plural:

• hjálpaði = helped (singular)
• hjálpuðu = helped (plural)

Even though each noun is singular by itself, together they count as plural.

It is past tense.

The verb is hjálpa (to help), and hjálpuðu means helped.

A few useful forms are:

• ég hjálpa = I help
• ég hjálpaði = I helped
• þau hjálpuðu = they helped

So in this sentence, the idea is that honesty and patience helped them.

Because the verb hjálpa takes the dative case in Icelandic.

So after hjálpa, you use a dative object:

• hjálpa mér = help me
• hjálpa þér = help you
• hjálpa þeim = help them

This is something English speakers often have to memorize, because English does not show this kind of case difference clearly in most nouns.

So:

• þeir / þær / þau = they
• þá / þær / þau = them (accusative)
• þeim = them (dative)

After hjálpa, the correct form is þeim.

Here að gera means to make or to make/do.

After hjálpa, Icelandic often uses að + infinitive to express help someone to do something:

• hjálpa einhverjum að læra = help someone to learn
• hjálpa einhverjum að skilja = help someone to understand
• hjálpa þeim að gera sambandið sterkara = help them make the relationship stronger

So að is the infinitive marker here, similar to English to.

Gera is a very common verb that can mean both do and make, depending on context.

In this sentence, it means make:

• gera sambandið sterkara = make the relationship stronger

This is a very common Icelandic pattern:

• gera eitthvað betra = make something better
• gera eitthvað auðveldara = make something easier
• gera eitthvað sterkara = make something stronger

So here gera is not just do in a vague sense — it is specifically make in the sense of causing a change.

Because -ið is the definite article attached to the end of the noun.

• samband = a relationship / relationship
• sambandið = the relationship

In Icelandic, the is usually not a separate word like in English. Instead, it is attached to the noun as a suffix.

Since samband is a neuter noun, the singular definite nominative/accusative form is sambandið.

It is accusative singular.

It is the direct object of gera:

• gera hvað? = make what?
• sambandið = the relationship

For this noun, the nominative and accusative singular happen to look the same:

• nominative: sambandið
• accusative: sambandið

So you cannot tell the case just from the ending alone here; you know it from its role in the sentence.

Because sterkara has to agree with sambandið, which is neuter singular.

The adjective comes from sterkur (strong), and sterkara is the comparative form used with a neuter singular noun in this kind of construction.

Compare:

• sterkari = stronger
• sterkara = stronger (neuter singular form / form used here)

Since sambandið is neuter singular, Icelandic uses:

• gera sambandið sterkara = make the relationship stronger

This is an example of adjective agreement in a predicative/result construction after gera.

Yes. It means stronger, not just strong.

The basic adjective is:

• sterkur = strong

The comparative is:

• sterkari / sterkara = stronger

So the sentence is talking about a change:

• not just that the relationship was strong,
• but that honesty and patience helped make it stronger.

Because in this construction, the adjective is not acting like a normal attributive adjective directly in front of the noun. It is functioning more like a result adjective or object complement after gera.

Compare the difference:

• sterka sambandið would be an adjective directly modifying a noun phrase
• gera sambandið sterkara means make the relationship stronger

In the second pattern, the adjective describes the resulting state of the object, so it does not take a separate definite article ending the way an attributive adjective would.

This is similar to English:

• the strong relationship
• make the relationship stronger

The basic order is:

Subject + Verb + Object + Infinitive phrase

So:

• Heiðarleiki og þolinmæði = subject
• hjálpuðu = verb
• þeim = indirect object / dative object
• að gera sambandið sterkara = infinitive phrase

A word-for-word structure is roughly:

• Honesty and patience helped them to make the relationship stronger

This is a very natural Icelandic sentence order.

Yes, Icelandic word order is somewhat flexible, but the verb usually follows the V2 rule in main clauses: the finite verb tends to come in the second position.

For example, if you begin with another element, the verb usually still stays second:

• Þeim hjálpuðu heiðarleiki og þolinmæði að gera sambandið sterkara.

That kind of variation is possible, but the original version is the most straightforward and neutral for learners.

So the sentence you have is a good standard model.

Yes, they are nouns, and both are abstract nouns:

• heiðarleiki = honesty
• þolinmæði = patience

They name qualities or traits rather than physical objects.

In the sentence, they are both in the nominative case because they are the subject.

Yes. The ending -leiki is a common Icelandic noun-forming ending that often creates abstract nouns, a bit like English -ness in some cases.

For example:

• heiðarlegur = honest
• heiðarleiki = honesty

So if you learn this pattern, it can help you recognize other abstract nouns too.

Þolinmæði is the noun patience.

It is related to the adjective þolinmóður (patient), though the forms are not as transparent to English speakers as some other noun/adjective pairs.

The important thing for this sentence is simply:

• þolinmæði = patience

Together with heiðarleiki, it forms a compound subject:

• Heiðarleiki og þolinmæði = honesty and patience

A rough English-friendly guide would be:

• Heiðarleiki ≈ HAY-thar-lay-kih
• þolinmæði ≈ THOH-lin-my-thee
• hjálpuðu ≈ HYOWL-poo-thu

A few pronunciation points:

• þ is like th in thing
• ð is like th in this
• æ is often like the vowel in my
• ei often sounds like ay
• hj at the start of a word has a sound English does not really have, but learners often approximate it with hy

These are only rough guides, but they can help you get started.

Yes, that is a very useful way to learn it.

A good pattern to memorize is:

• hjálpa + dative person + að + infinitive

Examples:

• Hann hjálpaði mér að læra. = He helped me study.
• Við hjálpuðum þeim að flytja. = We helped them move.
• Heiðarleiki og þolinmæði hjálpuðu þeim að gera sambandið sterkara.

If you learn the pattern as a chunk, it becomes much easier to build your own sentences.

There are three especially useful things to remember:

1. hjálpa takes the dative

   • so: þeim, not another form of them

2. A plural subject makes the verb plural

   • Heiðarleiki og þolinmæði → hjálpuðu

3. gera + object + comparative adjective means make something more ...

   • gera sambandið sterkara = make the relationship stronger

If you remember those three patterns, you will understand a lot of the sentence’s structure.