501 With bolder wing shall dare aloft to sty

sty > rise, soar

502 To the last praises of this Faery Queen;

last > (Speaking of that time when all 24 books of the poem will be complete)

503 Then shall it make more famous memory

memory > memorial; historical record

504 Of your heroic parts, such as they been:

parts > abilities, qualities been > [are; were]

505 Till then, vouchsafe your noble countenance

countenance > regard