Questions & Answers about Hyvää huomenta! Minä olen vielä väsynyt.
Why are hyvää and huomenta in the partitive case?
In Finnish, greetings and wishes like "Good morning!" are almost always in the partitive case. It is as if you are secretly saying "(I wish you a) good morning". The basic word hyvä becomes hyvää and huomen (an old word for morning) becomes huomenta.
Do I always need to include minä (I), or could I just say olen vielä väsynyt?
You can absolutely just say Olen vielä väsynyt. Because the verb ending in olen already tells us that "I" am the one who is tired, the pronoun minä is optional. Dropping the pronoun is very common in everyday Finnish.
Why isn't väsynyt (tired) in the partitive case too?
When you describe a whole person or thing using the verb olla (to be), the describing word stays in the basic form (the nominative case). Since you are describing yourself as a complete person, väsynyt does not get a partitive ending.
What exactly does vielä do in this sentence?
Here, vielä means "still" (I am still tired). It is a very common word placed right after the verb to show that a state is continuing. You will also see it used to mean "yet" or "more" in other contexts.