Chinese Idiom：杞人忧天（qǐ rén yōu tiān）

In the Spring and Autumn Period (chūn qiū 春秋时期,770-476 BC), in the State of Qi there was a man who always let his imagination run away with him. One day he even worried that the sky would falll on his head. He was so worried that he could neither eat nor sleep. Later, someone persuade him that his fears were groundless.This idioms satirizes those who worry unnecessary.

春秋战国时期，杞国有个人喜欢胡思乱想，一天，他竟然担忧天会塌下来，地会陷下去，自己无处存身。这个人越想越害怕，便整天愁眉苦脸，坐立不安，睡不好觉，吃不下饭。后来，有个人就去开导他，那个杞国人听后，才放下了心。成语杞人忧天讥笑那些没有必要或毫无根据的忧虑。

杞人忧天 (qǐ rén yōu tiān)
【翻译】The Man of Qi Who Worried That the Sky Would Fall.
【释义】用来讥笑那些没有必要或毫无根据的忧虑
【例句】我们做事要认真分析可能的出现困难，既不要杞人忧天，又不要粗心大意。
【近义词】庸人自扰
【反义词】无忧无虑、若无其事