Ordinal Numbers for intermediate learners
Imagine that you are on a list and you want to know where you are standing. To refer to that number, we use 'ordinal numbers.'
Why Do We Use Ordinal Numbers
We use ordinal numbers to show the position of something on a list or in a certain order.
How to Write Ordinal Numbers: 110
We usually add 'th' at the end of numbers in order to turn them into ordinal numbers. But one, two, and three are exceptions. Take a look at the list below:
Written  Numeral 

1 

2 

3 

4 
four 
5 
fif 
6 
six 
7 
seven 
8 
eigh 
9 
nin 
10 
ten 
Tip!
Pay attention to the spelling of ordinal numbers. The spelling of some numbers changes when we add 'th'. For example:
Five →
Eight →
Nine →
How to Write Ordinal Numbers: 1120
Just like ordinal numbers from four to ten, ordinal numbers from 11 to 20 get 'th' at the end. Take a look at this list:
Written  Numeral 

eleven 
11 
twelf 
12 
thirteen 
13 
fourteen 
14 
fifteen 
15 
sixteen 
16 
seventeen 
17 
eighteen 
18 
nineteen 
19 
twentie 
20 
Tip!
You can see that the spelling of some numbers changes. For example:
twelve → twelf
Twenty → twentie
How to Write Ordinal Numbers: Compound
When we want to write compound ordinal numbers, we use this form: the first part (cardinal number) + hyphen + second part (ordinal number)
Written  Numeral 

twentyfirst 
21 
twentysecond 
22 
twentythird 
23 
twentyfourth 
24 
twentyfifth 
25 
twentysixth 
26 
twentyseventh 
27 
twentyeighth 
28 
twentyninth 
29 
How to Write Ordinal Numbers: The Tens
As you saw before, when forming ordinal numbers, the letter 'y' at the end of the number changes into 'ie'. Take a look at the list below:
Written  Numeral 

ten 
10 
twent 
20 
thirt 
30 
fort 
40 
fift 
50 
sixt 
60 
sevent 
70 
eight 
80 
nint 
90 