Learn Finnish: Minulla on kaksi omenaa.

Finnish doesn't have a direct verb for "to have". Instead, you use the -lla or -llä ending (meaning "on" or "at") plus the verb on (is). So minulla on literally translates to "on me is".

Why is it omenaa instead of the regular plural omenat?

In Finnish, any number greater than one, such as kaksi, must be followed by the partitive singular form of the noun, not the plural. That is why we use omenaa (partitive singular) instead of omenat (nominative plural).

How do we get the partitive form omenaa from the base word omena?

For words ending in a single vowel like omena, you usually form the partitive by just adding an -a or -ä to the end. Because of vowel harmony, we add -a, making it omenaa.

Since there are two apples, why is the verb on (is) and not ovat (are)?

In the Finnish "to have" construction, the verb is always the third-person singular on, no matter how many things you own. Even though you have multiple apples, the verb does not change to plural.