Possible Clues:

• ". . . of ___ I sing"
• You, old-style
• 'Of ___ I Sing'
• "Of ___ I Sing"
• ''Of __ I sing''
• Fifth word of ''America''
• "... of ___ I sing"
• ''. . . of __ I sing''
• Friend's address
• 'America the Beautiful' pronoun