The fifth paragraph comes after Mrs. Mallard has heard the dreadfully upsetting news of her husband's death, and when she has ensconced herself in her bedroom to grieve by herself. Interestingly, we are told that the "storm of grief" that first possessed her when she first heard the news had passed, and it is clear that what she sees as she looks out of the window and what she hears from her bedroom are used to develop a very different mood that will come to characterise Mrs. Mallard's emotions. Note what this paragraph says and the imagery it contains:
She could see in the open square before her house the tops of trees that were all aquiver with the new spring life. The delicious breath of rain was in the air. In the street below a peddler was crying his wares. The notes of a distant song which some one was singing reached her faintly, and countless sparrows were twittering in the eaves.
Of course, the imagery of the trees being "all aquiver with the new spring life" finds its parallel in the state of freedom that she is able to enjoy. She, now that her husband has been taken for her, experiences "spring life." Likewise, the "delicious breath of rain" shows her sensuous enjoyment of nature, as does the "twittering" of the sparrows. In short the imagery employed in this paragraph shows us Mrs. Mallard's appreciation and enjoyment of nature and how much she has to look forward to. As the story itself is set in Spring, which is a time of re-birth and a new beginning, so Mrs. Mallard, so she believes, has been given a new beginning and the gift of freedom. Nature and the internal thoghts and feelings of Mrs. Mallard connect in this sense.