Example 1
The Nintendo Wii remote requires two AA batteries.
In this example, two is a cardinal adjective that counts the number of batteries needed to spend all of Sunday playing Mario Kart instead of going outside.
Example 2
Melissa visited seven countries on her recent Mediterranean cruise.
In this seafaring sentence, seven is a cardinal adjective that counts the number of countries where Melissa purchased postcards to mail back to her jealous, landlubber friends.
Example 3
Before his Latin American History exam, Derek stayed up for twenty-four hours straight.
While we admire Derek's ambition, Shmoop can't recommend his studying style. Here, the cardinal adjective twenty-four counts how many hours Derek spent wide awake, pounding Mountain Dew and reading about Emiliano Zapata.