think on your feet
US /θɪŋk ɑn jʊər fiːt/
UK /θɪŋk ɑn jʊər fiːt/

1.
隨機應變, 快速反應, 即興發揮
to be able to think and react quickly, especially in an unexpected situation
:
•
A good salesperson needs to be able to think on their feet.
一個好的銷售人員需要能夠隨機應變。
•
When the unexpected question came, she had to think on her feet to give a suitable answer.
當意想不到的問題出現時,她不得不隨機應變才能給出合適的答案。