This is the 10126th most frequent Swedish word.
imorgon
Tomorrow.
In this sentence, 'imorgon' is used as a subject complement to indicate the time (tomorrow) when the action of the sentence will occur.
Jag har en viktig möte imorgon.
I have an important meeting tomorrow.
Here, 'imorgon' functions as an adverbial specifying the time (tomorrow) at which the planned action (going to the sea) will happen.
Vi ska åka till havet imorgon.
We will go to the sea tomorrow.
In this instance, 'imorgon' acts as an object or topic for the verb 'planera,' referring to the time (tomorrow) that the planning concerns.