Related Clues:

• Time period
• Simple
• Word repeated before 'in' and 'out'
• Born yesterday, so to speak
• Jejune
• See 10-Down
• Time unit
• It breaks every morning
• It's close is signaled by 4-Down
• Ingenuous
• Easily duped
• Like a babe in the woods
• Certain trader
• Rotation period
• Unsuspecting