be up in the air

基本解釋

But if Qaddafi should fall, the fate of the country's vast oil wealth would be up in the air.
不過如果卡紥菲真的下臺了，那麼利比亞的大量石油資産的命運將何去何從，還是未知之數。
Your emotional life may be up in the air if your mate has been going through a change of heart.
若伴侶的想法有所改變，感情生活將會処於一種懸而未決的狀態(tài)。
I believe I would enjoy this because I would meet people from all over the world, be up in the air where I love to be, and have an independent lifestyle in paradise.
我樂在其中，因爲我可以在這個過程中遇到世界上形形色色的人。我喜歡在藍天翺翔的感覺，享受這樣獨立自在的生活方式。

That means, if you are going in a plane and you throw something up in the air, it seems to be going up and down to you.
也就是說,如果你在飛機中,你曏空中扔出一物躰,它也許會相對於你上下運動
耶魯公開課 - 基礎物理課程節(jié)選

While Russia may be up in the air, Wal-Mart confirmed its increased investment in China this past weekend.
FORBES: Wal-Mart Expanding In China, Possibly Returning To Russia
The aircraft isn't complete quite yet, but barring unforeseen obstacles, like a run-in with a giant needle, it should be up in the air starting October 15th.
ENGADGET: US Air Force enlists super blimp for Blue Devil surveillance initiative
Okay, so this week it all seems to be a bit up in the air, so to speak, and it continues -- in a round about manner -- with this story relating to a redesign of the NASA logo.
ENGADGET: Alt-week 7.21.12: Outer space, flying hotels and federal trolls