Localizers
Location and Position words form a group of specific Chinese words — localizers (方位词) — which we use to indicate the direction or exact position of an object.
How to use localizers
We use localizers after a noun to show the location of an object. In English such words are considered to play the role of prepositions and are located before nouns. For instance, on, under, in.
桌子上 
床下
床下
Pay attention
In colloquial speech there is no pause between a noun and localizers.
Scheme
object
localizer
Such a combination forms an adverbial modifier of a place and may answer the question “Where?”.
There are two groups of localizers: monosyllabic and disyllabic:
包里
包里面
包里面
Monosyllabic localizers
There are 10 monosyllabic localizers:
上
下
前
后
外
内
中
左
右
里
下
前
后
外
内
中
左
右
里 Examples
你的书在桌子上
Your book is on the table
nǐ de shū zài zhuōzi shàng
我的猫在椅子下
My cat is under the chair
wǒ de māo zài yǐzi xia
内 and 里 have similarities in their translations, so let’s compare them both:
里 is more often using in spoken speech , while 内 is mostly used in written speech.
Sometimes both of these may be substituted. For example, both sentences below are grammatically correct:
教室里上课
教室内上课
里 is used only with nouns denoting an exact object or building
包里
家里
内 means ‘within’. This localizer is used to denote some territory or area. 内 is only used with geographical objects, while 里 cannot be used with them.
国内
省内
教室内上课
里 is used only with nouns denoting an exact object or building
包里
家里
内 means ‘within’. This localizer is used to denote some territory or area. 内 is only used with geographical objects, while 里 cannot be used with them.
国内
省内 Pay attention
With specific geographical places we usually do not use any localizers at all. Instead, we use the word 在 .
Correct: 在中国 .
Incorrect: 在中国里.
.
Correct: 在中国 .
Incorrect: 在中国里.Besides indicating location, we use localizers to explain the time.
In such cases, they usually can be followed by words denoting the time or action phrases.
For example:
饭前
醒后
两个小时内
醒后
两个小时内 Disyllabic localizers
Apart from the word 中, we can add the words 边 , 面 , 头 , 方 after all monosyllabic localizers. They all mean "side".
In such cases, these localizers become nouns that indicate relative position.
For example:
左边
上面
后头
, 面 , 头 , 方 after all monosyllabic localizers. They all mean "side".
In such cases, these localizers become nouns that indicate relative position.
For example:
左边
上面
后头 Examples
学楼左边是图书馆
Library is on the left side of the school
xuélóu zuǒbiān shì túshūguǎn
桌子上面有一台电脑
There is a computer on the table
zhuōzi shàngmiàn yǒu yì tái diànnǎo
We also can use these words in collocations with directions:
东
西
南
北
西
南
北 Examples
蒙古国位于中国北边
Mongolia is located to the north of China
ménggǔguó wèiyú zhōngguó běibiān
There are the more words which we can only use in disyllabic form:
对面
旁边
中间
旁边
中间 Monosyllabic forms are usually used in combination with other words, while disyllabic forms can be used as nouns on their own.
Examples
外面下雨了
It’s raining outside
wàimiàn xià yǔ le
里边的小屋子
Inside the small cottage
lǐmiàn de xiǎo wūzi
Words with the indicating location may be used in combination with adverbs such as 更 and 最 .
and 最 .Examples
最上面的架子
The top shelf
zuì shàngmiàn de jiàzi
更前面一些的一个人
The guy up ahead
gèng qiánmiàn yìxiē de yí ge rén