Two third tones in a row
A third tone is low or dipping in isolation. Before another third tone, the first one is normally pronounced as a rising second tone. The spelling keeps the original third-tone mark so learners can see the underlying form.
Written nǐ hǎo; commonly pronounced ní hǎo.
Written hěn hǎo; the first syllable is usually rising in connected speech.
Wǒ yě hěn hǎo. — I am also well.
Do not force a full low-rise shape on both syllables. That creates a slow, unnatural rhythm and makes the contrast harder to hear.
不 changes before a fourth tone
The negative word 不 is normally fourth tone, bù. Before another fourth-tone syllable, it changes to a rising second tone, bú.
is not; the second syllable is fourth tone
not go; the verb starts with a fourth tone
Before other tones, keep the normal fourth tone: 不好 bù hǎo and 不来 bù lái. The change is predictable, not a new vocabulary item.
一 changes according to the next tone
The number 一 yī changes in connected speech. Before a fourth tone it is usually second tone, before a first, second, or third tone it is usually fourth tone, and when counting by itself it remains first tone.
- 一个 yí ge — one (before a light syllable)
- 一定 yí dìng — certainly; 一 is rising before fourth tone 定
- 一天 yì tiān — one day; 一 is falling before first tone 天
How to practice tone changes
- Write the dictionary Pinyin so you know the underlying form.
- Mark the spoken form above the phrase when practicing aloud.
- Record the complete phrase at normal speed, not only the changed syllable.
- Listen for pitch direction and rhythm; do not try to make every syllable equally long.
Tone changes make speech smoother without removing the meaning of the word. Clear rhythm and a strong contrast between important syllables matter more than exaggerated pitch movement.