Related Clues:

• Prompted on stage
• Reminded
• Handed a line
• Adjusted a Hummer's hum
• Harmonized
• Set the radio
• Did a garage job
• Accurately pitched
• Gave a hint to
• Fixed flats?
• Made a grand grander?
• Gave prompts
• Helped out, in a way
• Was prompter
• Told when to start, say