**Numbers** are generally used for specifying amounts and in mathematics: addition, subtraction, multiplication, and division. You have undoubtedly encountered them in many forms. Let’s first review *cardinal numbers*:

0 | zero | 21 | twenty-one |

1 | one | 22 | twenty-two |

2 | two | 30 | thirty |

3 | three | 40 | forty |

4 | four | 50 | fifty |

5 | five | 60 | sixty |

6 | six | 70 | seventy |

7 | seven | 80 | eighty |

8 | eight | 90 | ninety |

9 | nine | 100 | one hundred |

10 | ten | 101 | one hundred one |

11 | eleven | 102 | one hundred two |

12 | twelve | 200 | two hundred |

13 | thirteen | 500 | five hundred |

14 | fourteen | 1,000 | one thousand |

15 | fifteen | 2,000 | two thousand |

16 | sixteen | 10,000 | ten thousand |

17 | seventeen | 11,000 | eleven thousand |

18 | eighteen | 20,000 | twenty thousand |

19 | nineteen | 100,000 | one hundred thousand |

20 | twenty | 111,111 | one hundred eleven thousand one hundred eleven |

Careful! English names for certain large numbers differ from those in other languages:

English | Number |

million | 1,000,000 |

billion | 1,000,000,000 |

trillion | 1,000,000,000,000 |

When numbers are used in equations, there are specific mathematical terms to be used. In addition, numbers are combined by either the word *plus* or the word *and*: five plus three, ten and nine.

- In subtraction, the equation requires using the word
*minus*(–): ten minus four. - In multiplication, the equation requires using the word
*times*(×): six times three. - In division, the equation requires the phrase
*divided by*(÷ or /): twenty divided by five. - If an equation has an equal sign (=) in it, it is stated as
*equals*or*is*: two plus two equals four, six minus three is three. - If a number is a decimal, the decimal is expressed by the word
*point*: 6.5 is said as “six point five”; 10.7 is said as “ten point seven.”

The *ordinal numbers* are those that show a rank in a group or series. Most ordinals are formed by adding *-th* to the end of the number: *tenth*, *twentieth*, *sixty-seventh*, *hundredth*, and so on. But five ordinal numbers have special spellings which should be memorized:

- 1 = first
- 2 = second
- 3 = third
- 5 = fifth
- 12 = twelfth

Some example sentences with ordinal numbers:

- We have three daughters, but Denise was our first.
- The second seating for dinner is at 8:30 P.M.
- She was born on the twenty-fifth of June.

Dates are expressed in two ways: *May fifth* or *the fifth of May*. When giving a date as a number, it is most common to give the month before the day: 9/11 = September eleventh, 6/12 = June twelfth. In many other languages, the day precedes the month. This can cause confusion, because to some people 6/12 means “the sixth of December.” To English speakers it most commonly means “June twelfth.” To avoid such confusion, it is wise to give dates in this form: June 12, 2005.

Ordinals are also used to express fractions other than ½:

- ½ = one-half (not an ordinal)
- ¼ = one-fourth (
**Note:**One-fourth is sometimes expressed as “one-quarter” or “a quarter.”) - ⅓ = one-third
- 3/10 = three-tenths
- 14/25 = fourteen twenty-fifths (Notice the plural formation of the ordinal when the accompanying number is greater than one.)

Years that precede 2000 are expressed in two parts: 1850 is said as “eighteen fifty,”

1066 is said as “ten sixty-six.” The years that follow 1999 are said another way:

2000 | two thousand |

2001 | two thousand one, or twenty oh one |

2002 | two thousand two, or twenty oh two |

2010 | two thousand ten, or twenty ten |

2022 | two thousand twenty-two, or twenty twenty-two |

When saying on what date an event occurred, the word *on* is optional:

- The boy was born
*on*May first. - The boy was born May first.