Jag förväntar mig att paketet kommer i morgon.

Because the common Swedish verb is förvänta sig, which is a reflexive verb. That means it normally includes a reflexive pronoun:

• jag förväntar mig
• du förväntar dig
• han/hon förväntar sig

So mig here does not literally mean me in the usual object sense. It is part of the verb pattern.

English expect is not reflexive, but Swedish usually is here.

Here förvänta sig means to expect in the sense of to think something will probably happen.

So the sentence means that the speaker believes the package will arrive tomorrow.

Be careful not to confuse it with vänta på, which means to wait for. Those are different:

• Jag förväntar mig paketet i morgon = I expect the package tomorrow
• Jag väntar på paketet = I am waiting for the package

Att introduces a subordinate clause, like English that.

So:

• Jag förväntar mig att paketet kommer i morgon

literally has the structure:

• I expect that the package comes tomorrow

In natural English, that is often omitted, but in Swedish att is very common and natural in this kind of sentence.

Because paketet is the definite form, meaning the package.

The noun is:

• ett paket = a package
• paketet = the package

So the -et ending shows that the package is definite.

This is also a good reminder that paket is an ett-word.

Swedish often uses the present tense for future meaning when the time is clear from the context.

Here, i morgon already tells you the action is in the future, so kommer is perfectly natural.

This is very common in Swedish:

• Jag reser i morgon = I am leaving tomorrow
• Hon kommer nästa vecka = She is coming next week

So kommer does not have to mean present-time only.

Yes, you could say:

• Jag förväntar mig att paketet ska komma i morgon

But it is slightly different in feel.

• kommer is simple and natural when talking about something expected in the future
• ska komma can sound a bit more like is supposed to come or is meant to come

In many situations, both are possible, but kommer is very idiomatic here.

Because after att you have a subordinate clause, and Swedish subordinate clauses do not follow normal main-clause inversion rules.

In a main clause, Swedish often puts the verb in second position. But after att, the subject usually comes before the verb:

• att paketet kommer i morgon

not

• att kommer paketet i morgon

So this word order is exactly what you should expect in a subordinate clause.

Yes. Swedish often uses komma in contexts where English might prefer come, arrive, or be delivered, depending on the situation.

So paketet kommer i morgon is a natural way to say that the package will arrive tomorrow.

You could also hear more specific verbs in other contexts, such as anlända, but komma is very common and natural in everyday speech.

Yes. Both i morgon and imorgon are used.

Many learners first meet i morgon as two words, but imorgon is also common in modern Swedish.

In this sentence, the time phrase is placed at the end, which is very natural:

• Jag förväntar mig att paketet kommer i morgon

That end position is the most neutral one here.

Not if you want the same meaning.

Jag förväntar mig att paketet kommer i morgon means I expect the package to arrive tomorrow.

If you say väntar på, you are talking about waiting, not expecting. For example:

• Jag väntar på paketet = I am waiting for the package

So förväntar sig is the right choice when the idea is about expectation rather than the act of waiting.