Related Clues:

• Unaffected - innate
• Normal - instinctive
• Unaffected - native
• Unaffected - musical note
• Normal - innate - instinctive
• Unspoilt
• Instinctive - not surprising
• Not affected
• Normal - genuine
• Expected - appropriate - artless
• Fuel from underground
• (In music) neither sharp nor flat
• Reason for death when not suspicious
• Without affectation
• Not flat, say