cold feet在什么时候(语境)用的多?

cold feet
失去信心或勇气, 胆怯

例句与用法:
1. He got cold feet at the last minute.
他事到临头却退缩了.

2. She got cold feet when asked to recite in class.
当她被叫起来在班上背诵时害怕了。

3. I volunteered to do a parachute jump to raise money for charity but I got cold feet at the last minute and didn't to through with it.
为慈善事业筹集资金我自愿参加跳伞，可是在最后一刻我临阵害怕了，结果没有完成任务。