Examples:

• Can you call back later?
• Can you call back later?
• Can you call back later?
• Can you call back later?
• Can you call back later?
• Can you call back later? I can't talk now.
• Can you call back later? I'm at work.
• Can you call back later? I'll be available after six.
• Is Jill there? - I'm sorry. Can you call back later? We are eating now.