* Simple and Direct: "I've been feeling blue ever since my best friend moved away."
* With a Reason: "The rain and the gray skies made me feel blue."
* With a Solution: "I was feeling blue after the breakup, but spending time with my family helped."
* Figurative: "The city felt blue and lonely after everyone left for the holidays."
* Informal: "Don't worry, I'm just feeling a little blue today. It'll pass."