夹起尾巴 jiāqǐ wěiba
(1) [tail between his legs]∶狼狈
咱们老实,才会有恶霸,咱们敢动刀,恶霸就夹起尾巴跑
(2) [modest]∶虚心
他兢兢业业,廉洁奉公,虽多次受到上级表扬,仍然极为谦卑地夹起尾巴