Learn Swedish: Frågorna är svåra. - The questions are difficult.

Fråga (question) is an en-word that ends in -a. To make it plural, we drop the -a and add -or, making frågor (questions). To say the questions, we add the definite plural suffix -na to the end, giving us frågorna.

Why does svåra have an -a at the end?

In Swedish, adjectives must match the noun they describe. Because frågorna is plural, the adjective svår (difficult) gets an -a added to the end to become the plural form svåra.

Does every plural noun get -na for its definite (the) form?

Not always! While plural nouns ending in -or, -ar, or -er usually take the -na ending (like frågorna), ett-words that end in a vowel take -a, and ett-words that end in a consonant take -en.