When the green woods laugh with the voice of joy
And the dimpling stream runs laughing by
When the air does laugh with our merry wit
And the green hill laughs with the noise of it
When the meadows laugh with lively green
And the grasshopper laughs in the merry scene
When Mary and Susan and Emily
With their sweet round mouths sing "Ha, ha he!"
The second stanza continues the patern of the first. Note Blake’s use of soft  alliterative  ‘l’s. All the senses are appealed to throughout the poem. In this line the colour 'green’ is described as ‘lively’ — an example of  synaesthesia , in which movement and colour are descriptively merged.
Laughing Song