Learn Finnish: Olemme saarella elokuussa. - We are on the island in August.

To say that something happens "in" a certain month, you add the inessive case ending -ssa or -ssä. Since elokuu has back vowels (a, o, u), it takes -ssa, becoming elokuussa (in August).

Are all months formed like elokuu?

Yes, all Finnish months end in the word kuu, which means "moon" or "month". Elo relates to "harvest" or "life", making August the "harvest month". When you add -ssa to any month, it always attaches to the kuu part.

Why do we use -lla for the island but -ssa for the month?

The ending -lla usually means "on" a surface, so saarella translates to "on the island". The ending -ssa means "in" or "inside". Even though both are location endings, Finnish specifically uses the "in" ending (-ssa) for months.

The dictionary word for "island" is saari. Why does it change to saare- in saarella?