ER vs LIANG: A Complete Guide to Understanding 二 (èr) and 两 (liǎng) in Chinese

Are you confused about when to use 二 (èr) and when to use 两 (liǎng) in Chinese? It can be tricky for Chinese beginners as both er and liang are translated as ”two” in English. Then, what’s the difference between 二 (èr) and 两 (liǎng)? Luckily for you, you have this article, which will guide you through how to understand and use each, with examples!
Let’s dive in!
The Difference between 二 (èr) and 两 (liǎng)
Essentially, both 二 (èr) and (liǎng) mean “2”, it’s just that they are used for different circumstances in Chinese. To put it short: 二 (èr) is the “2” for numbers and 两 (liǎng) is the “2” for measure words.
I know it sounds very abstract right now. But hang on! Once we get to the details, it will make sense.
When to Use 二 (èr) for 2?
二 (èr) is generally used in numbers, such as when you do the counting, perform mathematical operations, give your telephone number, etc.
Let’s find out how to use 二 (èr) properly in Chinese in these circumstances.
1. Use 二 (èr) to Tell Numbers, Count and Do Math
Let’s see some examples!
- 一二三四五
yī èr sān sì wǔ
one two three four five
- 十二
shí èr
twelve
- 二十二
èr shí èr
twenty-two
- 八十二
bā shí èr
eighty-two
- 十二个人
shí èr gè rén
twelve people
- 二十二块钱
èr shí èr kuài qián
twenty-two RMB (Kuai: basic monetary unit of China)
- 二点五
èr diǎn wǔ
two point five
- 三分之二
sān fēn zhī èr
two-thirds
- 二加二等于四
èr jiā èr děng yú sì
two plus two equals four

If the digit 2 is part of another number, big or small, you can read it as 二 (èr).
Examples:
- 20
二十
èr shí
- 200
二百
èr bǎi
- 0.2
零点二
líng diǎn èr
That said, there are some occasions where you can read the 2 in a number as 两 (liǎng) as well. I’ll get to that in a minute.
Now, when the digit 2 appears in a series of numbers, you always read it as 二 (èr). That’s why you only hear 二 (èr) in a telephone number.
For example, if your phone number is 802-4226-5372, you read it as 八零二 四二二六 五三七二 (bā líng èr sì èr èr liù wǔ sān qī èr).
2. Use 二 (èr) to Express “2nd”
In addition to cardinal numbers, 二 (èr) is constantly used to express the ordinal number “second”.
Examples:
- 第二
dì èr
the second
- 第二个
dì èr gè
the second one
- 第二次
dì èr cì
the second time
- 第二天
dì èr tiān
the second day
- 第二周
dì èr zhōu
the second week
- 二楼
èr lóu
the second floor
- 二哥
èr gē
the second oldest brother
- 二月
èr yuè
February (the second month)
- 二号
èr hào
the second date (of the month)
- 二月二十二号
èr yuè èr shí èr hào
February twenty-second (the twenty-second date of the second month)

When to Use 两 (liǎng) for 2?
When you want to express a quantity of things (and by using a measure word to do so), you will need to use 两 (liǎng) instead for 2. In other words, use 两 (liǎng) for “two” when you need to say “two of something”.
Pattern
两 (liǎng) + measure word
Let’s take a look at some examples!
- 两只猫
liǎng zhī māo
two cats
- 两位老师
liǎng wèi lǎoshī
two teachers
- 两本书
liǎng běn shū
two books
- 两个月
liǎng gè yuè
two months
- 两周时间
liǎng zhōu shíjiān
two weeks of time
- 两块钱
liǎng kuài qián
two RMB (Kuai: basic monetary unit of China)
- 两岁
liǎng suì
two years of age
- 两次
liǎng cì
two times
- 两个小时
liǎng gè xiǎoshí
two hours
- 两个孩子
liǎng gè háizi
two kids

As you can see, there is always a measure word after 两 (liǎng).
Just to be clear, I am talking about the 2 as the isolated cardinal number 2 here, as in “two of something”. 两 (liǎng) does not function as the ordinar number “2nd”, regardless of whether a measure word is used or not. Stick with 二 (èr) if you want to say “2nd of something”.
Examples:
- √ 两个人 liǎng gè rén
two people
- × 第两个人 dì liǎng gè rén
Never use 两 (liǎng) for the 2nd!
- √ 第二个人 dì èr gè rén
the second person
- √ 两天 liǎng tiān
two days
- × 第两天 dì liǎng tiān
Again, never use 两 (liǎng) for the 2nd!
- √ 第二天 dì èr tiān
the second day
Numbers containing the digit 2 (e.g 12, 20, 22) can be read without changing the 二 (èr) sound when expressing a quantity (and it’s wrong to read the 2 as 两 (liǎng) in these numbers, even if the 2 appears directly before a measure word).
- × 二个孩子 èr gè háizi
Never use 二 (èr) for “two of something”!
- √ 两个孩子 liǎng gè háizi
two kids
- × 十两个孩子 shí liǎng gè háizi
Don’t switch to 两 (liǎng) if 2 is only part of a number!
- √ 十二个孩子 shí èr gè háizi
twelve kids
- × 二岁 èr suì
Again, never use 二 (èr) for “two of something”!
- √ 两岁 liǎng suì
two years of age
- × 八十两岁 bā shí liǎng suì
Again, don’t switch to 两 (liǎng) if 2 is only part of a number!
- √ 八十二岁 bā shí èr suì
eight-two years of age
When Do 二 (èr) and 两 (liǎng) Not Matter?
Here’s the tricky part (but believe me, it actually makes things easier for learners). In some cases, the line between 二 (èr) and 两 (liǎng) can be very vague that you can just forget about the grammar rules and use whichever version of 2 you like.
Here are the two most common scenarios when 二 (èr) and 两 (liǎng) can be used interchangeably.
1. Before Metric Numbers
According to the general rule, the number 200, should be read as 二百 (èr bǎi). I mean, it’s just a number and there is no measure word behind it, right?
But more often than not you will hear native speakers read it as 两百 (liǎng bǎi). And for the number 2,000 and 20,000, there is at least an 80 % chance that you’ll hear them say 两千 (liǎng qiān) and 两万 (liǎng wàn) instead of 二千 (èr qiān), 二万 (èr wàn).
From a grammatical point of view, if you think of the metric numbers 百 (bǎi), 千 (qiān), 万(wàn) as measure words for numbers (which is correct), it all makes sense. But this is not really about the grammar, it’s more about colloquial habit.
To native speakers, some word combinations just sound better than others. It just feels more natural to slip 两百 (liǎng bǎi), 两千 (liǎng qiān), 两万 (liǎng wàn) into a conversation, than 二百 (èr bǎi), 二千 (èr qiān), 二万 (èr wàn). While there is absolutely no problem to read the 2 as 二 (èr) in those numbers, it could sound a bit too formal in a casual conversation. You are more likely to hear er on news or in a math lesson.
- 222
二百二十二
èr bǎi èr shí èr
the grammatically perfect, textbook version
两百二十二
liǎng bǎi èr shí èr
the more favored version in spoken Chinese
- 2,222
二千二百二十二
èr qiān èr bǎi èr shí èr
textbook version
两千两百二十二
liǎng qiān liǎng bǎi èr shí èr
spoken version
- 22,222
二万二千二百二十二
èr wàn èr qiān èr bǎi èr shí èr
textbook version
两万两千两百二十二
liǎng wàn liǎng qiān liǎng bǎi èr shí èr
spoken version
2. Expressing 2 o’clock

Another potentially confusing example is the case of “2 o’clock”.
Some teachers might tell you 两点 (liǎng diǎn) is the correct way to express it. They even dig out the reason why you have to change 二 (èr) to 两 (liǎng) from the grammatical perspective. (yes, if you think of 点 (diǎn) as the measure word for the points on the clock, everything makes sense)
But this is not true. Both 二 (èr) and 两 (liǎng) are commonly used to express 2’o clock. Again, this has more to do with colloquial habit than grammar. As you can guess, 两点 (liǎng diǎn) does sound more natural than 二点 (èr diǎn) to native speakers, but really, either is fine.
Well, there are a few other cases where you can use 二 (èr) and 两 (liǎng) interchangeably in Chinese, but let’s stick to the basics for now and save them for the future. As a general rule (not the law though), you can use 二 (èr) when you want yourself sound serious and authoritative, and 两 (liǎng) when just want to be a happy, chatty folk.
Using 二 (èr) or 两 (liǎng): Regional Variations
It’s an interesting fact, people from Southern China use 两 (liǎng) much more often than their compatriots in the north.
As you are probably aware, there are thousands of dialects in China, and these dialects have a strong influence on how people speak Mandarin (I am talking about the choice of vocabulary, not accents).
Take Shanghai, for example, the local dialect of Shanghai uses only liang and ni (which is not a word in Mandarin) for 2, and there is not really an equivalent word for the er in Mandarin. Consequently, when people in Shanghai speak Mandarin, they would use lots of 两 (liǎng), and very few 二 (èr) out of habit.
For instance, you will most likely to hear them say 两月 (liǎng yuè) instead of 二月 (èr yuè) for February (the second month), and 两楼 (liǎng lóu) instead of 二楼 (èr lóu) for the second floor.
People from northern China, however, tend to overuse 二 (èr) when 两 (liǎng) is supposed to be used. For instance, in Beijing, you will likely hear 二位 (èr wèi) instead of 两位 (liǎng wèi) for two people (honorific), even though according to the grammar rule, 两 (liǎng) should be used to express a quantity.

Well, I am not trying to mess your mind here, on the contrary, I encourage you to follow the grammar rules I explained: using 二 (èr) for 2nd, and 两 (liǎng) for measure words, then you’ll speak perfect Mandarin.
But let’s just say if you occasionally see native speakers use 二 (èr) where 两 (liǎng) is expected (or vice versa), don’t be surprised! It’s not that they are wrong. That’s just how Mandarin is spoken in different parts of China! (and the variation is perfectly understood across the country)
二 (èr) and 两 (liǎng) Practice
Ready for some 二 (èr) and 两 (liǎng) practice? Here we go!
1. 我有 ____ 个哥哥。
Wǒ yǒu ____ gè gēge.
- 二 (èr)
- 两 (liǎng)
2. 我的爸爸 _______ 岁。
Wǒ de bà ba _______ suì.
- 四十二 (sì shí èr)
- 四十两 (sì shí liǎng)
3. 我家在 ______ 楼。
Wǒ jiā zài ______ lóu.
- 二十二 (èr shí èr)
- 二十两 (èr shí liǎng)
4. 请给我 ____ 杯水。
Qǐng gěi wǒ ____ bēi shuǐ.
- 二 (èr)
- 两 (liǎng)
5. 现在是下午 ____ 点四十分。
Xiànzài shì xiàwǔ ____ diǎn sì shí fēn.
- 二 (èr)
- 两 (liǎng)

Answers:
- 两 (liǎng) I have two elder brothers.
- 四十二 (sì shí èr) My dad is 42 years of age.
- 二十二 (èr shí èr) My home is on the 22nd floor.
- 两 (liǎng) Please give me two glasses of water.
- 二 (èr)/两 (liǎng) Now it’s 2:40 pm.
Grammar Summary: ER or LIANG
- Both 二 (èr) and 两 (liǎng) mean “2” in Chinese. They are used for different circumstances.
- 二 (èr) is used to tell numbers, count, do math & express 2nd.
- 两 (liǎng) is used to express “two of something”
- 二 (èr) and 两 (liǎng) are interchangeable before metric numbers & when expressing 2 o’clock
- Some regional differences exist in China, but people always understand, so no biggie!
Remember, grammar is the glue that holds the pieces of language together, so don’t forget to check other grammar articles on ImproveMandarin.Com’s Grammar Channel! 谢谢 (xièxie) for reading this post!