一下子

• Pinyin: yī xià zi
• Hanzi breakdown: 一 = one; 下 = down/time; 子 = suffix intensifying the sudden nature

Meaning

All at once; all of a sudden; in one go. Indicates something happening suddenly or instantly.

Emphasizes the rapidity or immediacy of an action or change. Often expresses surprise at how quickly something happened. Can modify both actions (一下子跑了) and changes of state (一下子变了). More emphatic than 一下 alone.

Examples

1. 天气一下子变冷了，大家都没准备好。 The weather suddenly turned cold, and nobody was prepared.
2. 他一下子吃了五个包子，把我们都吓到了。 He ate five baozi all at once, shocking us all.
3. 房价一下子涨了这么多，年轻人根本买不起。 Housing prices shot up so much all of a sudden — young people simply can't afford them.

Usage Guide

Context: suddenness, surprise, everyday

Tone: emphatic

Do Say

• 他一下子就明白了。(He understood all at once.)
• 一下子来了这么多人！(So many people came all of a sudden!)

Don't Say

• 我一下子慢慢走 (Contradictory — 一下子 means sudden/fast, can't pair with 慢慢)

Origin & History

Compound of 一 (one), 下 (down, time measure), and 子 (suffix). Emphasizes a single, sudden moment.

Cultural Context

Generation: All ages

Social background: Universal