Which pair of uses of figurative language from “the caged bird” support the extended metaphor of freedom versus oppression?

The first two stanzas contrast two birds. Lines 1 through 7 describe the actions of a bird that is free; it interacts with nature and “dares to claim the sky.” The second stanza (lines 8 through 14) tells of a captured bird that must endure clipped wings, tied feet, and bars of rage; yet he still opens his throat and sings.The third and fifth stanzas are identical. Lines 2, 4, and 6 and lines 5 and 7 of these identical stanzas rhyme. This repeated verse elaborates on the song of freedom trilled by the caged bird; though his heart is fearful and his longings unmet, the bird continues to sing of liberty. The fourth stanza continues the comparison of two birds, the caged and the free. The free bird enjoys the breeze, the trees, the winds, the lawn, the sky, and the fat worms; the caged bird with his wings still clipped and his feet still tied continues, nevertheless, to open his throat and sing.  So, "the caged bird sings" - "the free bird thinks"  help support the extended ,etaphor of freedom versus oppresion. 

d.  dawn bright lawn; grave of dreams   correct edg21

Explanation: