Translation:Tomorrow morning we will eat breakfast together.
You are right. It is commonly used, however it can also refer to later in the future as well.
For example, maybe you are planning an upcoming weekend getaway with your partner. When explaining the plans, you may say "in the morning we can go to this restaurant."
In that specific case, it's not necessarily talking about tomorrow but rather a day in the future.
Should the form "imorgon" also be accepted maybe? http://dinsvenska.se/ordformer/ska-i-dag-skrivas-isar-eller-ihop/ Or is it a common misspelling?
No, actually, borde would sound really weird here, like "do you think there's a reason that perhaps we should?"
Using ska vi äta frukost tillsammans i morgon? is perfectly natural and only means ska as in the future tense construction, not as in the obligation.
Guys there's something I don't get. How is it even necessary to use SKA here? I morgon bitti is tomorrow morning so it should express the future tense itself, shouldn't it? I guessed I morgon bitti äter vi frukost tillsammans already meant that we are doing that like, tomorrow, in the future?
- morgon = morning
- i morgon = tomorrow
- i morgon bitti = tomorrow morning
It looks odds, but English has done essentially the same thing with "morrow" meaning "morning" turning into "tomorrow" for the next day. And bitti is from bittida, literally "by time", meaning "in time" - which eventually changed meaning to "early".
Hence, it's literally "to morrow early in time", so to speak.