The ode opens as a kind of overdose and ends with the word 'forlorn'. Track how the bird's song moves from the garden, into the past, and back again.
My heart aches, and a drowsy numbness pains My sense, as though of hemlock I had drunk, Or emptied some dull opiate to the drains One minute past, and Lethe-wards had sunk:
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My heart aches and a drowsy numbness dulls my senses, as if I had drunk poison, or drained some dull opiate a minute ago and was sinking toward the river of forgetfulness.
Thou wast not born for death, Bird! No hungry generations tread thee down;
Underlined words and phrases can be tapped for a note
You were not born to die, immortal bird. No hungry generations of people have trampled you down.
That's the whole thing.
Read it again slowly — it gets better the second time.