What does "if not" mean in English for Spanish?

In English for Spanish, "if not" means:

si no

Listen to "if not": (If you have an HTML5 enabled browser, you can listen to the native audio below)

This is a phrase that is used in the GamesForLanguage English for Spanish Language Game in the following scenes:

• English for Spanish 3, Level 1, Scene 5
• English for Spanish 3, Level 1, Scene 6
• English for Spanish 3, Level 1, Scene 10
• English for Spanish 3, Level 1, Scene 11
• English for Spanish 3, Level 1, Scene 12