Think on your feet
Definition 1 of 1
Pro Tip 1/3Sudden Scenarios
Understand it's used when someone must quickly analyze a situation and act without prior planning. 
During the debate, he had to think on his feet to counter the unexpected arguments.
Pro Tip 2/3Job Interviews
In interviews, 'think on your feet' means to respond well to unusual or difficult questions. 
She impressed the interviewers with her ability to think on her feet when faced with tough scenarios.
Pro Tip 3/3Quick Decisions
It's often related to decision-making under pressure, showing composure and confidence. 
As a nurse in the ER, you must think on your feet to make life-saving decisions.