Up in the air - 悬而未决、不确定、未知 对话1 Emily: Have you heard anything about our project deadline? 关于咱们项目的截止日期，你有听说什么吗 James: Not really. Everything is still up in the air since the manager hasn’t made a decision yet. 没有，啥都没定呢，因为经理还在考虑 对话2Emma: Have you finalized your vacation plans yet?你的度假计划敲定了吗？Jake: Not yet. Everything is still up in the air because we're waiting to see if we can get time off from work.还没有。啥都还没定，因为我们在等着看能否请到假。