Learn Turkish: Yeşil elbise yeni değil. - The green dress is not new.

Just like in English, adjectives in Turkish are placed immediately before the noun they describe. So, yeşil elbise forms the phrase "green dress". If we swapped the order to say elbise yeşil, it would turn into a full sentence meaning "the dress is green".

Is there a word for "the" missing before yeşil?

Turkish doesn't have a definite article like the English word "the". A phrase like yeşil elbise can mean "a green dress" or "the green dress" depending on context. Because it is the subject being discussed in this sentence, "the" is the most natural translation.

Where is the word for "is" in this sentence?

In Turkish, you don't always need a direct equivalent for "is" in the present tense, especially for "he/she/it" subjects. Placing the subject (yeşil elbise) and the description (yeni değil) next to each other is enough to mean "The green dress is not new."

Why do we use değil to say "not" here instead of a negative suffix?

The standalone word değil is used to negate adjectives and nouns (like saying something is not new or not a dress). You only use negative suffixes like -me or -ma when you are negating action verbs, like "do not go" or "do not eat".