Luftbubblan skapade sprickan.

Because Swedish, like German, very often forms compound nouns by joining words together.

• luft = air
• bubbla = bubble
• luftbubbla = air bubble

Then the definite ending is added to the whole compound:

• luftbubbla = an air bubble
• luftbubblan = the air bubble

This is very normal in Swedish. English often writes these as separate words, but Swedish usually combines them.

That -n is the definite singular ending for many en-words in Swedish. It works like English the.

In this sentence:

• luftbubblan = the air bubble
• sprickan = the crack

Their base forms are:

• en luftbubbla
• en spricka

Since both are common-gender nouns (en words), their definite singular forms take -n:

• luftbubbla → luftbubblan
• spricka → sprickan

In Swedish, the definite article is usually attached to the end of the noun instead of standing alone before it.

So:

• sprickan literally contains the idea of the crack
• luftbubblan literally contains the idea of the air bubble

A separate word like den is usually used when there is also an adjective:

• sprickan = the crack
• den stora sprickan = the big crack

So in your sentence, no separate den is needed.

skapade is the past tense of skapa, which means to create.

So:

• skapa = to create
• skapar = creates / is creating
• skapade = created

In the sentence:

• Luftbubblan skapade sprickan.
• The air bubble created the crack.

No. Swedish verbs do not change for person the way English verbs sometimes do.

For example, in the present tense:

• jag skapar = I create
• du skapar = you create
• han/hon skapar = he/she creates
• de skapar = they create

The verb form stays the same. That makes Swedish verb conjugation simpler than English in this respect.

Yes, this sentence uses the basic Swedish word order:

• Subject + Verb + Object

So:

• Luftbubblan = subject
• skapade = verb
• sprickan = object

That is directly parallel to English:

• The air bubble
  • created
    • the crack

So the structure is very straightforward here.

Yes, that would also be possible, but it means something slightly different.

• Luftbubblan skapade sprickan = the air bubble created the crack
  This suggests a specific air bubble and a specific crack, probably already known from context.

• En luftbubbla skapade en spricka = an air bubble created a crack
  This sounds less specific and introduces them as new information.

So the definite forms here are about context and specificity, not just grammar.

A rough pronunciation guide for an English speaker is:

• Luftbubblan ≈ LUFT-bub-lan
• skapade ≈ SKAH-pa-de
• sprickan ≈ SPRIK-an

A few notes:

• u in luft is not exactly like English u; it is more rounded.
• sk before a is usually a hard sk sound, so skapade starts like ska-.
• sprickan has a short i, like in sit, not like machine.

The main stress is usually on the first syllable of each word:

• LUFTbubblan
• SKApade
• SPRICkan

The dictionary forms are:

• luftbubbla = air bubble
• skapa = to create
• spricka = crack

In the sentence, they appear in these forms:

• luftbubblan = definite singular of luftbubbla
• skapade = past tense of skapa
• sprickan = definite singular of spricka

So if you wanted to look them up, you would usually search for luftbubbla, skapa, and spricka.

Sometimes, yes, depending on context.

The verb skapa literally means create, so created is the direct translation. But in natural English, if an air bubble produced a crack in a material, English might often say:

• The air bubble caused the crack.

So created is grammatically correct and literal, while caused may sound more natural in some contexts. The best choice depends on the situation and the style of translation.