Numeral adjectives are those that express numbers. They include one, two, three, first, second, and many others.
Numeral adjectives are divided into:

• cardinal adjectives that denote how many.

  For example

  one life
  three blind mice
  five important ideas

• ordinal adjectives that show which one of a series.

  For example

  the first chapter
  the fourth commandment
  the third floor

• multiplicative adjectives that show the number of repetitions

  For example

  twice thought
  thrice tried, once achieved.

When a numeral is uses as a noun, the cardinal, like the pronominal adjectives, takes no article. On the other hand, the ordinal uses the article.

For example

Two only were present.
The third was lost.

At this point proceed to Exercise 9.