Here's a breakdown:
* Sad: Feeling or showing sorrow, unhappiness, or regret.
* Sadder: More sorrowful, unhappy, or depressing than something else.
* Saddest: The most sorrowful, unhappy, or depressing of all.
Examples:
* "That was the saddest movie I've ever seen."
* "The saddest day of my life was when my dog died."
* "Her voice was filled with the saddest tone I'd ever heard."
"Saddest" can be used to describe:
* Emotions: A feeling of deep sorrow, despair, or grief.
* Events: A situation or occurrence that causes sadness.
* Objects: Something that evokes a sense of sadness.
* Music, stories, etc.: Art forms that are designed to evoke sadness.