THE FIX: One reason to use the proper cup is kitchen tidiness. Liquid measuring cups are usually glass or plastic with a handle and a spout. They allow you to pour the liquid so that it reaches the measurement line without overflowing. Dry measuring cups hold the exact amount and are designed to be leveled o with a flat edge—filling the cup with liquid can easily result in spillage. Here’s the bigger issue: ounces. Liquid measuring cups indicate that 1 cup equals 8 ounces, but really it means 1 cup of liquid equals 8 fluid ounces. Dry ingredients like flour and sugar vary in weight. For example, 1 cup of all-purpose flour weighs 4.5 ounces, not 8. For dry ingredients, weigh the ingredient or use the dry cup measurement called for in the ingredient list to make sure you get the correct amount.