Hon märkte att papperskorgen var full, så hon tömde den direkt.

Märkte is the past tense of märka.

In this sentence, märkte means noticed or realized.
So hon märkte att ... means she noticed that ...

Att means that and introduces a subordinate clause.

So:

• Hon märkte att papperskorgen var full
  = She noticed that the trash can was full

In English, that is often omitted, but in Swedish it is very common to keep att in sentences like this.

Because after att, Swedish uses subordinate clause word order.

In a main clause, Swedish often puts the finite verb in second position.
But in a subordinate clause introduced by att, the order is more like:

• subject + verb

So:

• att papperskorgen var full

not

• att var papperskorgen full

A very useful thing to remember is that subordinate clauses do not follow the usual main-clause V2 pattern.

It is a compound noun:

• papper = paper
• korg = basket
• papperskorg = wastepaper basket / trash can / bin

Then -en is the definite ending, so:

• papperskorg = a wastepaper basket
• papperskorgen = the wastepaper basket

In everyday English, this is often translated simply as the trash can or the bin, depending on context.

Because Swedish usually adds the definite article to the end of the noun.

So:

• en papperskorg = a trash can
• papperskorgen = the trash can

This is one of the big differences from English. Instead of putting the in front, Swedish often attaches the definite ending directly to the noun.

Because plain definiteness is usually shown just with the ending:

• papperskorgen = the trash can

If you say den papperskorgen, it often sounds more like that trash can.

Also, Swedish uses den/det/de together with a noun when there is an adjective:

• den fulla papperskorgen = the full trash can

So in this sentence, papperskorgen by itself is the normal form.

Because papperskorg is an en-word.

Swedish pronouns agree with the gender of the noun:

• en noun → den
• ett noun → det

So:

• en papperskorg
• hon tömde den

If it were an ett-word, you would use det instead.

Because full agrees with papperskorgen, which is a singular en-word.

Predicate adjectives in Swedish change form depending on what they describe:

• en word singular: full
• ett word singular: fullt
• plural: fulla

So:

• papperskorgen var full
• glaset var fullt
• korgarna var fulla

Since papperskorgen is an en-word, full is correct.

Because var full describes a state: the trash can was full.

• var full = was full
• blev full = became full

In this sentence, she notices the condition of the trash can. It is already full at that point, so var full is the natural choice.

Tömde is the past tense of tömma.

It means emptied.

So:

• hon tömde den direkt
  = she emptied it right away

Depending on context, English might sometimes say she took it out, but the Swedish verb literally means empty.

Here så means so, and it is acting as a coordinating conjunction linking two main clauses:

• Hon märkte att papperskorgen var full
• så hon tömde den direkt

Because så is linking the clauses, the clause itself still has normal main-clause order:

• hon tömde

not

• tömde hon

So the pattern is:

• clause 1 + så
  • clause 2

This is different from cases where an adverb is placed first inside a clause and causes inversion.

Here direkt means immediately, right away, or straight away.

So:

• hon tömde den direkt
  = she emptied it immediately

It adds the idea that she did it without delay.

That is a very natural position for it in Swedish.

The sentence structure here is:

• hon = subject
• tömde = verb
• den = object
• direkt = adverb

So:

• hon tömde den direkt

This is a normal and idiomatic way to say she emptied it right away.

Not always. Så has several uses in Swedish.

It can mean things like:

• so
• then
• like this / in this way
• so / very in expressions like så stor = so big

In this sentence, though, it clearly means so, showing a result:

• the trash can was full, so she emptied it

Yes, depending on context.

For example:

• papperskorg often suggests a wastepaper basket or indoor bin
• soptunna is more like a garbage bin / trash can, often larger
• sopkorg can also be used for a trash bin

So papperskorgen is perfectly natural here, but other words are possible if the situation is different.

Not always.

In Swedish, a comma before a coordinating conjunction like så can be used to make the sentence easier to read, especially when the clauses are a bit longer. In a short sentence, it is often optional.

So both of these can be acceptable:

• Hon märkte att papperskorgen var full, så hon tömde den direkt.
• Hon märkte att papperskorgen var full så hon tömde den direkt.

The version with the comma gives a clearer pause.