"The yellow sponge is in the sink."
Translation:L'éponge jaune est dans l'évier.
Try reporting it because we don't know which sink is intended from the English sentence: "l'évier" is the kitchen sink and "le lavabo" is the bathroom sink, washbasin or washbowl. https://dictionary.reverso.net/english-french/sink
However, "lavabos" can also mean "lavatory" or washroom which is another name for a public restroom. http://www.larousse.fr/dictionnaires/francais-anglais/lavabo/46361
First, éponge is feminine, so it would be La jaune éponge est dans l'évier. Second, putting adjectives in French before the nouns means that they are subjective. When you say la jaune éponge, it means that you see it as yellow, but it's not necessarily yellow. Since colors are not subjective, we don't put color adjectives before the nouns in French.
N.B.: There is also a poetic interpretation. When you say la jaune éponge, it means that all sponges are always yellow anyway, but you consider that the color of the sponge is important for literary purposes.