Sponsorns bidrag ökade överskottet.

Because Swedish normally forms the genitive with a plain -s, not with an apostrophe like English.

So:

• the sponsor = sponsorn
• the sponsor’s = sponsorns

This is standard Swedish spelling.

Because two things are happening at once:

1. sponsor is the base noun.
2. -n makes it definite: sponsorn = the sponsor
3. -s adds the genitive: sponsorns = the sponsor’s

So sponsorns is literally the sponsor + ’s, but written the Swedish way.

After a possessive or genitive in Swedish, the following noun is usually in the indefinite form.

So Swedish says:

• min bok = my book
• Peters bil = Peter’s car
• sponsorns bidrag = the sponsor’s contribution

Even though the whole phrase is definite in meaning, the noun bidrag itself stays indefinite because the possessive already makes the reference specific.

Because it refers to a specific surplus, and Swedish usually marks definiteness with a suffix on the noun.

• ett överskott = a surplus
• överskottet = the surplus

Since överskott is an ett-word, its definite singular ending is -et.

Ökade is the past tense of öka.

Common forms are:

• infinitive: öka
• present: ökar
• past: ökade
• supine: ökat

So this sentence is talking about something that happened in the past.

No. Swedish verbs do not change for person or number.

So the past tense ökade stays the same with different subjects:

• jag ökade
• vi ökade
• bidraget ökade

That makes Swedish verb conjugation simpler than English in this respect.

In this sentence:

• Sponsorns bidrag = the subject
• ökade = the verb
• överskottet = the direct object

So the structure is the normal Swedish word order:

Subject + Verb + Object

This is one reason the sentence is understood as the sponsor’s contribution increased the surplus, not the other way around.

The nouns are:

• en sponsor → common gender
• ett bidrag → neuter
• ett överskott → neuter

This matters because gender affects forms like the definite ending:

• sponsorn
• bidraget
• överskottet

In the sentence, bidrag happens to appear without its definite ending because it follows a genitive phrase: sponsorns bidrag.

Yes. Öka can be both:

• intransitive: something increases
• transitive: something increases something else

Examples:

• Överskottet ökade. = The surplus increased.
• Sponsorns bidrag ökade överskottet. = The sponsor’s contribution increased the surplus.

So in your sentence, öka is being used transitively.

The Swedish ö does not have an exact English equivalent.

A useful approximation is:

• say something like the vowel in British English bird,
• but without the r,
• and with rounded lips.

A few extra notes:

• In ökade, the first ö is long.
• In överskottet, the first ö is also long.
• The sk in överskottet is pronounced as a clear sk sound here, because it comes before o.

If you want a rough learner-friendly guide:

• ökade ≈ UR-kah-deh, but with rounded lips on the first vowel
• överskottet ≈ UR-ver-skot-et, again with rounded lips on the first vowel

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