3. • The tone of a word sometimes changes when used in a
sentence, depending on the tone of the word that precedes
or comes after it.
4. Rule 1
• If a 3rd tone is followed by a 3rd tone, the first 3rd tone
becomes a 2nd tone (3+3 → 2+3).
5. Example:
nǐ hǎo → ní hǎo (hello)
hěn hǎo → hén hǎo (very good)
hǎo jiǔ → háo jiǔ (good wine)
shuǐ ɡuǒ → shuí ɡuǒ (fruit)
• Note: The word is still written with two third tones, although
the first syllable is read in second tone.
6. Rule 2
• The word bù 不（no; not） has the 4th tone, but when it is
followed by another 4th tone, it becomes 2nd tone. (4+4 → 2+4)
7. Example:
bù cuò → bú cuò (not bad)
bù qù → bú qù (not go)
bù duì → bú duì (wrong)
bù dàn → bú dàn (not only)
• Note: To simplify, “不” is marked in the fourth tone “bù” in
Chinese dictionary entries. In Chinese textbooks, on the other
hand, it is marked according to the actual pronunciation.
9. 1. The word yī 一 （one）is 1st tone when:
①yī comes at the end of a word.
Example:
wàn yī : in case
wéi yī : only
②it acts as an ordinal number to indicate the number “one.”
Example:
yī bān : Class One
yī nián jí : Grade One
yī hào : the first day of month
dì yī mínɡ : the first place
10. 2.yī is pronounced with 4th tone when
preceding 1st, 2nd, or 3rd tones.（yī → yì）
Example:
yī tiān → yì tiān (one day)
yī zhí → yì zhí (always)
yī bǎi → yì bǎi (hundred)
11. 3.yī is pronounced with 2nd tone when
preceding a 4th tone. （yī → yí)
Example:
yī cì → yí cì (one time, once)
yī ɡònɡ → yí ɡònɡ (altogether)
yī wàn → yí wàn (ten thousand)
