"Je voudrais une robe à manches courtes pour l'été."

Translation: I would like a short-sleeved dress for summer.

[DOette]

When do we avec versus à

[PKE26318]

The "à" indicates that the sleeves are part of the dress and that the sleeves which belong to the dress are short; the "à" indicates that the sleeves are part of the whole, not a separate entity. It is a similar case with foods such as "le gâteau au chocolat" (chocolate cake) or " les pâtes au fromage et aux champignons" (cheese and mushroom pasta), for example. After all, you can't remove the chocolate from the cake or the cheese and mushrooms from the pasta once it is added. So in other words, "à" is used to indicate composition.

"Avec" is used to indicate accompaniment (je vais avec vous), cause (je n'entends pas le professeur avec ce bruit), addition (Voudrais-tu du vin avec ton dîner?), with a noun to translate many English adverbs (avec joie = joyfully), and with some expressions (se fâcher avec quelqu'un).

[InvertedGo]

Possibly it is the difference between "a short-sleeved dress" and "a dress with short sleeves".

[--Roody--]

Both mean the same thing and both are accepted.

[HPGFU]

Why is "want" not accepted in place of "would like"?

[Alvaro362299]

Basically:
je voudrais = I would like (Conditionnel Présent)
je veux = I want (Indicatif Présent)