2. I'm not sure. 我不確定。
3. Who knows? 誰知道啊?
4. Don't ask me! 別問我!
5. It's not certain. 還不確定。
6. Nothing is set yet. 事情都還沒有定案。
7. It hasn't been decided yet. 還沒有決定呢。
8. It's not clear. 事情還未明朗。
9. It's up in the air. 情況還混沌未明。
10. It's hard to say. 很難說。