up in the air
尚未確定；懸而未決
口語·表示計劃或決定未定
英文釋義
Uncertain or undecided; not yet determined or settled
例句
Our vacation plans are still up in the air due to the weather.
典故來源
源自事物懸浮空中的意象，比喻決定或結果尚未確定。