Definition
To do something with very little preparation but with the hope of succeeding.
准备不充分但又希望成功
The project had almost no budget, and they were operating on a wing and a prayer.
这个项目几乎没有预算，他们只能凭着一线希望来进行。
She entered the competition on a wing and a prayer, having not practiced enough.
她凭着一线希望参加了比赛，但练习得并不够。
With the deadline looming and resources scarce, they had to complete the task on a wing and a prayer.
随着截止日期逼近且资源匮乏，他们只能凭着一线希望完成任务。