Explain the idioms in bold. Which are positive/negative?

Explain the idioms in bold. Which are positive/negative? Are there similar idioms in your languages? 1. She seems to be on cloud nine after getting her degree.2. The party was great. Everyone seemed ti be in high spirits.3. Despite all her problems, she's trying to keep her chin up.4. He almost jumped out of his skin when I tapped him on the shoulder.