Here's a breakdown:
* Skylark: This bird is often associated with soaring, joyful song. In the poem, the skylark sings "above the infant band," suggesting a sense of elevation and innocence.
* Thrush: The thrush is also known for its beautiful song, but it is often seen as more grounded and connected to nature than the skylark. In the poem, the thrush "in the greenwood tree" provides a backdrop of peaceful melody, highlighting the natural world that surrounds the children.
Together, these birds symbolize the pure and unburdened happiness of youth. Their songs create a sense of carefree merriment, echoing the carefree nature of the children playing on the green.
It's also worth noting that both birds are associated with nature's renewal and cyclical life. The skylark's song is often heard in the springtime, symbolizing new beginnings, while the thrush's song is associated with the lush green of summer, reflecting the ongoing cycle of life.
Ultimately, the skylark and thrush in "Echoing Green" serve as vivid auditory imagery, enriching the poem's themes of childhood innocence, joy, and the interconnectedness of nature and human experience.