Numbers
If math describes how the world works, numbers are the alphabet that makes math possible. In this lesson, we will discover all about them.
How Do We Use Numbers in English?
There are two common kinds of numbers:
 Cardinal Numbers
 Ordinal Numbers
Cardinal Numbers
Cardinal numbers (also called cardinals) are used to show a general number of people, animals, or things such as two, six, twelve, five hundred. They show how many of those things or people there are.
Placement
Cardinal numbers are commonly used as determiners. In other words, they are typically used before nouns.
I love my pets. I have
When used as a determiner, they can also take predeterminers such as articles or possessive determiners before them. For example:
My
We can use cardinal numbers with the structure:
cardinal numbers + of + determiners
Tip!
Cardinal numbers can also be used as nouns:
People came to the theater in
Numbers Bigger Than Twenty
If you want to write numbers bigger than twenty, you should use a hyphen between parts of the compound number. In other words, hyphenate all compound numbers from twentyone through ninetynine. For example:
Numbers Bigger Than 100
With numbers bigger than 100, you should use a hyphen between compound numbers after the word 'and.'
For 100, we can either use the definite article 'a' or use 'one.'
a/one hundred and
eight hundred and
In American English, people normally do not use the word 'and':
three hundred fiftysix
Numbers Bigger Than 1,000
For numbers bigger than 1,000, put a hyphen between compound numbers and use the word 'and'. You can
use either the definite article 'a' or 'one' for 1,000.
Remember to use a comma to separate three digits → 80,000.
a/one thousand (and) one hundred (and) twentyone
In American English and is mostly not used.
three hundred (and) five thousand (and) two hundred (and) thirtyfour
Number 0
The number 0 has many names:
 in telephone numbers, codes, etc. →
oh  in measurements and temperature →
zero  in British English →
nought  in sports commentary →
nil  in tennis →
love
What Are Ordinal Numbers?
Ordinal numbers are used to show the position of something in a list or in a row, that's why we call them ordinal. Here are a few examples:
This is the
She is the
How to Make Ordinal Numbers?
Most of the numbers get th at the end to change to an ordinal number except the first three numbers. Check out the table below:

twentie 

thirtie 

fortie 
four 
fiftie 
fif 
sixtie 
six 
seventie 
seven 
eightie 
eigh 
ninetie 
nin 
hundred 
ten 
thousand 
Now let us take a look at the numbers that have two parts such as twentyone:
twentyfirst  one hundred and thirtyfirst 
twentysecond  two hundred and fortyfifth 
twentythird  three hundred and fiftyseventh 
When Do We Use Ordinal Numbers?
Ordinal numbers are used in many different cases as follows:
 fractions
 Roman numbers
 telling the dates
 talking about centuries
Here are a few examples for each:
fraction
Alice III → Alice the
Roman number
My birthday is on June the
telling the dates
The castle was built in the
talking about centuries
How to Write Ordinal Numbers
When we want to write the ordinal numbers in the number form you should use the last two letters in a smaller form after the cardinal number, for example:
 first = 1st
 second = 2nd
 third = 3rd
 fourth = 4th