Questions & Answers about Juon vain vahvaa kahvia.
Why are both vahvaa and kahvia in the partitive case?
This is adjective agreement in action! Kahvi (coffee) is an uncountable liquid, so when you drink an unspecified amount of it, it takes the partitive case: kahvia. Because adjectives must match the case of the nouns they describe, the adjective vahva (strong) must also take the partitive case, becoming vahvaa.
Will the adjective always get the exact same ending letters as the noun?
Not always! The adjective and the noun must both be in the same case (like the partitive), but the actual letters added might differ depending on the word's base form. In this sentence, both vahva and kahvi just happen to belong to word groups that form the partitive by simply adding an -a.
Where is the word for "I" (minä) in this sentence?
It is built right into the verb! Juon means "I drink." Because the -n ending already makes it perfectly clear who is doing the action, the pronoun minä can be safely dropped. This is very common in Finnish.
Why is vain placed after the verb instead of at the beginning?