knife-edge/'naɪfedʒ/

n 用作单 刀刃；锋利的东西

词组on a knife-edge

1. 处于不确定的状态

• The success or failure of our project is still on a knife-edge. 我们的项目成败尚未可知。

2. 十分焦急地

• He was waiting for his interview result on a knife-edge. 他焦急不安地等着面试结果。