突然的 (tú rán de) is the Mandarin Chinese pronunciation for the Engpsh word "sudden." The word "sudden" comes from the Old French word "soudain," which means "sudden" or "unexpected." Here are some example sentences in Engpsh and their translations in Chinese:

"The sudden noise startled me." (这突然的噪声吓了我一跳。)
"The sudden change in weather caught us off guard." (天气的突然变化让我们措手不及。)
"She had a sudden headache." (她突然头痛。)

I hope this helps!