Lines 1-2

Swallows are small, fast birds known for being gregarious—that is, for socializing with other birds and forming large colonies. They also are known for the long distances of their migrations. When the speaker of this poem infers that someone who is unidentified, referred to as "they," could turn her little girl into a bird, she is speaking metaphorically, by referring to aspects of the swallow that the girl would have if she went through such a transformation. In this case, the fear expressed is that the girl will, as she grows up, start socializing with others of her kind and fly away, traveling with them rather than staying near her home. Moreover, the speaker is not just worried that her girl will turn into a swallow, but that "they" will turn her into one. Readers naturally wonder to whom this refers. At first, it appears...