http://ichinesematters.blogspot.com/2016/10/tone-changes.html

1. Tone sandhi [3] [3] ⇒ [2] [3]
1) 语法yǔfǎ (grammar)
2) 雨伞yǔsǎn (umbrella)
3) 保养Bǎoyǎng (maintenance)
4) 洗脸xǐliǎn (wash face)
5) 广场guǎngchǎng (public square)
6) 老鼠lǎoshǔ (mouse)
7) 老虎lǎohǔ (tiger)
8) 勇敢yǒnggǎn (brave)


2. yī 一（one）

The word yī 一 （one）is 1st tone when used as part of a number.

E.g. yī 一 （one）, èr 二 （two）, sān 三 （three）…

• But yī 一 （one） is pronounced with 4th tone when preceding 1st, 2nd, or 3rd tones.

E.g. Yī tiān is pronounced yì tiān 一天 (one day)

Drills:
yì zhī jī
一只鸡
a chicken

yì jiā rén
一家人
a family

yì jiān jiàoshì
一间教室
a classroom

yì bāo yān
一包烟
a package of cigarettes



yì jié kè
一节课
a lesson

yì píng jiǔ
一瓶酒
a bottle of wine

yì tiáo hé
一条河
a river

yì tóu niú
一头牛
a cow



yì kǒu rén
一口人
a person in a household

yì wǎn fàn
一碗饭
a bowl of rice

yì suǒ xuéxiào
一所学校
a school

yì zhǒng yǔyán
一种语言
a kind of language



• Yī is pronounced with 2nd tone when preceding a 4th tone.

E.g. Yīcì is pronounced yícì 一次 （one time, once）

Drills:
yí wèi lǎoshī
一位老师
a teacher

yí gè gēge
一个哥哥
an older brother

yí zuò dàlóu
一座大楼
a big building

yí kuài xiàngpí
一块橡皮
an eraser

3. bù 不

The word bù 不（no） has the 4th tone, but when it is followed by another 4th tone, it becomes 2nd tone.

E.g. bù shì 不是 （is not） is pronounced búshì

Practices:
bù duō
不多
not a lot

bù'ān
不安
unease

bù zhīdào
不知道
do not know



bùnéng
不能
can not

bùxíng
不行
no/ it does not work. (colloquial)

bùchéng
不成
no/ it does not work. (dialect)

bù míngbái
不明白
do not understand clearly



bù hǎo
不好
not good

bù xǐhuān
不喜欢
do not like

bù kěyǐ
不可以
can not
(to be not allowed to do something)

bù dǒng
不懂
do not understand


búshì
不是
to be not

búhuì
不会
can not (do not know how to do something)

búqù
不去
do not go

búpà
不怕

not afraid