Daily Chinese Idiom Guessing Game
Constant and unpredictable changes in a situation or circumstances.
象风云那样变化不定。比喻时局变化迅速，动向难以预料。
南朝·梁·庾信《入彭城馆》诗年代殊之民俗，风云更盛衰。”
The business world is full of fengyun bianhuan, so you must always be adaptable.