most of the time, sweets mean candies, like mints, chocolates, etc.

cakes

When you feel it is your or others' responsibility to do something or say something, you can use 应该. For example, when it is raining heavily outside but the windows of your house are still open and the big wind blows the rain water into your house, then you or someone else 应该 close all your windows. You can also make suggestions with the word 应该. For example, when you find your friend wears strangely and that looks bad, you can remind him or her, he or she 应该 change his or her clothing style. When you make predictions, you can also use 应该. For example, a disgusting boy destroyed a garden, his neighbors may predict that he 应该 not come back again.