Learning English Numbers: What Are Cardinal Numbers?
Digits
Begin the number lesson plan by teaching the English digits. A digit is the number symbol for the numbers in a number system, e.g., 1 (one) and 3 (three). Digits combine to form numerals, which are symbols that represent numbers, e.g., 1 (one) and 13 (thirteen). The ten digits in English are:
- 0 – zero
- 1 – one
- 2 – two
- 3 – three
- 4 – four
- 5 – five
- 6 – six
- 7 – seven
- 8 – eight
- 9 – nine
The ten English digits also correspond to the first ten numbers in English: zero (1) through nine (9). English language learners must memorize the names of and symbols for the ten digits in English.
Ten, Eleven, Twelve, and Teens
Continue by teaching the next ten English numbers, which are ten (10) through nineteen (19). Ten (10), eleven (11), and twelve (12) are irregular and must simply be memorized:
- 10 – ten
- 11 – eleven
- 12 – twelve
The numbers thirteen (13) through nineteen (19) are the teens, so named because of the _-teen_ suffix at the end of the number:
- 13 – thirteen*
- 14 – fourteen
- 15 – fifteen*
- 16 – sixteen
- 17 – seventeen
- 18 – eighteen
- 19 – nineteen
The teens are formed by affixing the -teen suffix onto the digits three (3) through nine (9). However, note the slight spelling and pronunciation changes in thirteen (13) and fifteen (15): three (3) becomes thir- and five (5) becomes fif-.
Multiples of Ten
After teaching the first twenty English numbers, teach the English learners the multiples of ten. To form the multiples of ten in English, affix the -ty suffix to the digit:
- 20 – twenty*
- 30 – thirty*
- 40 – forty*
- 50 – fifty*
- 60 – sixty
- 70 – seventy
- 80 – eighty
- 90 – ninety
Again note the slight spelling and pronunciation changes in twenty (20), thirty (30), forty (40) and fifty (50). Point out that the same change in thirteen (13) and fifteen (15) occurs in thirty (30) and fifty (50): three (3) becomes thir- and five (5) becomes fif-. Point out the similarity between twelve (12) and twenty (20). Finally point out that only the spelling changes in forty (40).
Two Digit Numbers
After teaching the first twenty numbers and the multiples of ten, explain how to form the other two digit numbers. All numbers between twenty-one (21) and ninety-nine (99) are formed by combining the multiple of ten with a digit between one (1) and nine (9). For example:
- 21 – twenty-one
- 22 – twenty-two
- 33 – thirty-three
- 45 – forty-five
- 57 – fifty-seven
- 98 – ninety-eight
Explain that the two digit numbers in English are written with a hyphen between the multiple of ten and the digit.
Higher Numbers
Next teach the words for the higher numbers:
- X00 – hundred
- X,000 – thousand
- X,000,000 – million
- X,000,000,000 – billion
- X,000,000,000,000 – trillion
All higher numbers are regular in that the number is spoken as the digit followed by the name of the higher number. A comma is placed between every three digits beginning from the right. For example:
- 100 – one hundred, a hundred
- 200 – two hundred
- 1,000 – one thousand, a hundred
- 4,000 – four thousand
- 20,000 – twenty thousand
- 1,000,000 – one million, a million
- 13,000,000,000 – thirteen billion
Complex Higher Numbers
Finally teach how to form more complex higher numbers, which are formed by combining the names of the higher numbers with the names for the numbers under one hundred from the left to the right. For example:
- 101 – one hundred one, one hundred and one
- 135 – one hundred thirty-five
- 1,002 – one thousand two, one thousand and two
- 3,579 – three thousand five hundred seventy-nine
- 7,654,321 – seven million six hundred fifty-four thousand three hundred twenty-one
For a printable study sheet of the English cardinal numbers, please download English Cardinal Numbers Study Sheet.
This post is part of the series: English Numbers
The articles in this ESL series explain how to teach forming, speaking, reading, writing, and spelling numbers in English including cardinal numbers, ordinal numbers, fractions, and decimals.