Read this extract from Mariana, and then answer the question that follows it: And ever when the moon was low, And the shrill winds were up and away, In the white curtain, to and fro, She saw the gusty shadow sway. But when the moon was very low, And wild winds bound within their cell, The shadow of the poplar fell Upon her bed, across her brow. She only said, 'The night is dreary, He cometh not,' she said; She said, 'I am aweary, aweary, I would that I were dead!' All day within the dreamy house, The doors upon their hinges creak'd; The blue fly sung in the pane; the mouse Behind the mouldering wainscot shriek'd, Or from the crevice peer'd about. Old faces glimmer'd thro' the doors, Old footsteps trod the upper floors, Old voices call'd her from without. She only said, 'My life is dreary, He cometh not,' she said; She said, 'I am aweary, aweary, I would that I were dead!' The sparrow's chirrup on the roof, The slow clock ticking, and the sound Which to the wooing wind aloof The poplar made, did all confound Her sense; but most she loathed the hour When the thick-moted sunbeam lay Athwart the chambers, and the day Was sloping toward his western bower. Then, said she, 'I am very dreary He will not come,' she said; She wept, 'I am aweary, aweary, O God, that I were dead!' How does Tennyson make these lines so sad?