In the ballad Greensleeves, this stanza is repeated after every four lines.

Greensleeves was all my joy,
Greensleeves was my delight,
Greensleeves was my heart of gold,
And who but Lady Greensleeves.

What is this group of lines called?

metaphor

alliteration

refrain

imagery

The correct answer is "refrain." A refrain is a regularly recurring phrase or verse within a poem or song. In the case of Greensleeves, the stanza "Greensleeves was all my joy..." is repeated after every four lines, making it a refrain.