Have cool feet 或 get cold feet 指对一个计划或一件事情紧张，甚至不想去做了。

他本来是要表白爱意的，可事到临头他却胆怯得什么也没有说。Hewas going to confess his love but he got cold feet and said nothing.

你还想跟这个生气的顾客对话吗，还是胆怯得不想说了？Areyou still ready to talk to this angry customer ？ or are you having cold feet？.