冷不丁 (lěng bú) — suddenly, out of the blue, without warning

Definition

Examples

• 他冷不丁问了我一个问题，我愣住了。
  Tā lěng bú wèn le wǒ yí gè wèn tí, wǒ lèng zhù le.
  He suddenly asked me a question, and I was stunned.
• 外面冷不丁下起了大雨，我们都没带伞。
  Wài miàn lěng bú xià qǐ le dà yǔ, wǒ men dōu méi dài sǎn.
  It suddenly started pouring outside, and none of us had umbrellas.
• 她冷不丁笑了起来，把大家都吓了一跳。
  Tā lěng bú xiào le qǐ lái, bǎ dà jiā dōu xià le yí tiào.
  She burst out laughing out of nowhere, startling everyone.