Tone Changes for 一 (yī)
The most versatile tone-changing character
Category: Tones & Pronunciation
The Rule
一 (yī) is 1st tone alone, becomes 4th tone (yì) before 1st/2nd/3rd tones, and becomes 2nd tone (yí) before 4th tone.
Why This Matters
一 has the most complex tone change rules in Chinese, but they follow a clear pattern. When counting or at the end of a phrase, it stays 1st tone. Otherwise, it adapts to what follows. English speakers find this tricky because the same character has three possible pronunciations depending on context.
Examples
• 一天 (yì tiān) — "one day" [一 becomes 4th tone before 1st tone 天] • 一年 (yì nián) — "one year" [一 becomes 4th tone before 2nd tone 年] • 一起 (yì qǐ) — "together" [一 becomes 4th tone before 3rd tone 起] • 一个 (yí gè) — "one (of something)" [一 becomes 2nd tone before 4th tone 个] • 第一 (dì yī) — "first / number one" [一 stays 1st tone at the end of a word]
Common Mistakes
❌ Always pronouncing 一 as yī in all contexts ✅ Adapt the tone based on what follows: yì or yí → 一样 (yí yàng, same) needs 2nd tone because 样 is 4th tone. Saying yī yàng sounds foreign. ❌ Confusing 一's rules with 不's rules ✅ 一 has more rules: it changes before 1st, 2nd, 3rd (→ 4th) AND before 4th (→ 2nd). 不 only changes before 4th. → Remember: 一 adapts to everything, 不 only reacts to 4th tone.
Quick Tip
Rule of thumb for 一: before 4th tone → say yí, before anything else → say yì, alone or counting → say yī.
Rule of thumb for 一: before 4th tone → say yí, before anything else → say yì, alone or counting → say yī.
Examples
Common Mistakes
Incorrect: Always pronouncing 一 as yī in all contexts → Correct: Adapt the tone based on what follows: yì or yí. 一样 (yí yàng, same) needs 2nd tone because 样 is 4th tone. Saying yī yàng sounds foreign.
Incorrect: Confusing 一's rules with 不's rules → Correct: 一 has more rules: it changes before 1st, 2nd, 3rd (→ 4th) AND before 4th (→ 2nd). 不 only changes before 4th.. Remember: 一 adapts to everything, 不 only reacts to 4th tone.
Quiz
How is 一样 (same) pronounced?