Translation:We wear green hats with red shoes.
You'll catch on. It has to be plural because she says "des" and not "un/une". "Un/une" is the indefinite article, like "a/an" in English. In English, in the plural, we can say "some", but we often just skip the article - "some green hats" or just "green hats", but in French the plural article is "des" and it is required. HTH.