Tennyson uses visual imagery and auditory descriptors to further themes of isolation which propel the narrative of "The Lady of Shalott."
Consider the visual imagery in the beginning of the poem:
On either side the river lie
Long fields of barley and of rye,
That clothe the wold and meet the sky;
And thro' the field the road runs by
To many-tower'd Camelot;
The yellow-leaved waterlily
The green-sheathed daffodilly
Tremble in the water chilly
Round about Shalott.
Willows whiten, aspens shiver.
The sunbeam showers break and quiver
In the stream that runneth ever
By the island in the river
Flowing down to Camelot.
There is a vivid, living, natural world outside the confines of the Lady of Shalott's imprisonment. And the colors of the natural world stand in sharp contrast to the "four gray walls" that hold her.
She desperately longs to be part of this world and to break free from her imprisonment. She longs for human connection and is "half sick of shadows" resulting from existing instead of living.
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