杞人忧天qǐrén-yōutiān
(1) 《列子·天瑞》:“杞国有人忧天地崩坠，身亡所寄，废寝食者”。传说杞国有个人怕天塌下来，愁得寝食不安
英:like the man of Qi who was haunted by the fear that the sky might…