心有余悸 -------- A burned child dreads the fire.

例句：
A: It's said that you had a narrow escape from the car accident, didn't you?
据说，你在车祸中死里逃生，是吗？
B: Yes, I did and I still feel that a burned child dreads the fire.
是的，我至今仍感到心有余悸。

同义词：
Once bitten, twice shy.