"Un placard" may be either a cupboard or a closet. These terms are applied quite differently in different regions of the English-speaking world. "Un armoire" may be a piece of furniture in which one hangs clothes, variously called a closet, a wardrobe, or simply an armoire. Take a look here:
I translated placard as "cabinet." I don't know anyone who uses the word "cupboard" anymore, at least in my part of the world.