Questions & Answers about Lahje on polven alla.
Why does polvi (knee) become polven in this sentence?
It is in the genitive case because it comes right before the postposition alla (below/under). In Finnish, the vast majority of spatial postpositions require the noun attached to them to take the genitive -n ending.
How do we know to use alla instead of alle or alta to describe this position?
Alla describes a static location, meaning where something currently is. Because the trouser leg is just resting below the knee, we use alla. If you were pulling the trouser leg down to that position, you would use alle to show movement towards the space below the knee.
What happens to the -i at the end of polvi when it becomes polven?
Polvi is an old Finnish word ending in -i. For these older words, the final -i changes to an -e- when you add endings. This gives us the stem polve-, to which we add the genitive -n.
Why use the word lahje instead of housut here?
Housut is a plural word referring to the entire pair of trousers or pants. Lahje is the specific vocabulary word for one single trouser leg. If you were talking about both legs being rolled up or positioned, you would use the plural lahkeet.