Learn Croatian: Žene su pametne.

In Croatian, adjectives must match the noun they describe in gender and number. Since žene (women) is a feminine plural noun, the adjective takes the feminine plural ending -e. If we were talking about one woman, we would use the singular form pametna.

Does the noun žene also end in -e because it is plural?

Yes! The singular word for woman is žena. For most feminine nouns that end in -a in the singular, the plural ending changes to -e. Notice how the noun and the adjective match perfectly here: žene pametne.

Why is su placed right after the first word?

su (are) is a short, unstressed word called a clitic. In Croatian, clitics have a strict rule: they almost always want to be in the second position of a sentence, which in this case is right after žene.

Why is there no word for "the" before žene?

Croatian doesn't have articles like "a" or "the". Depending on what you are talking about, Žene su pametne can translate to "Women are smart" (women in general) or "The women are smart" (a specific group of women you already mentioned).