Final answer:
Without additional context, it's not possible to definitively answer who takes Moira's part in the duet, as the question seems to pertain to a specific narrative or adaptation not provided in the excerpt. The excerpt given is from Wordsworth's 'The Solitary Reaper' and doesn't reference a character named Moira or a duet.
Step-by-step explanation:
The query, 'Who takes Moira's part in the duet?' appears to reference a literary piece or a specific context of a narrative, where an individual named Moira is expected to participate in a duet. Without additional context, it is difficult to identify the specific work or the character who would replace Moira in the duet. However, the excerpt provided seems to be from William Wordsworth's poem 'The Solitary Reaper', which describes the poet's musings upon hearing a solitary Highland lass singing while reaping in the fields.
The poem itself shares the poet's reflections and wonders about the song the reaper is singing, suggesting it may be about 'old, unhappy, far-off things, And battles long ago'. The poem does not mention a character named Moira or a duet, which implies that your question may be related to a different text or a specific adaptation or analysis of Wordsworth's poem where a character named Moira is involved.