That's an iffy question 这是个假设性问题(恕不回答)
in an iffy situation 处于前途未卜的局面
Are you joining us for lunch? -I'm iffy about it at the moment. 你要跟我们一块儿去吃午饭吗?-我这会儿还没拿定主意呢
The chances of passing the exam are iffy. 能否通过这个考试还是个未知数.