To add to the very significant phrases from Kate Chopin's "The Story of an Hour" that have already been posted, here are others:
She would have no one follow her.
This phrase about no one following her is the very first indication of the independence of Mrs. Mallard as she has wept with "sudden, wild abandonment" and then turned to climb the stairs.
The delicious breath of rain was in the air.
Louise Mallard senses things more now that she is free from the repression of her husband. She looks to the West, the future, and delights freely the sounds of nature.
When she abandoned herself a little....
Mrs. Ballard is beginning to emerge as a person herself.
A kind intention or a cruel intention made the act seem no less a crime as she looked upon it in that brief moment of illumination.
Louise Ballard experiences her "awakening" as she realizes that she is free to be her own person, no longer repressed by her Victorian husband.
There was a feverish triumph in her eyes, and she carried herself unwittingly like a goddess of Victory.
Louise Mallard feels that she has won back her identity; she is free and independent of all that made her the wife of Brently Mallard. The suggestion of war with these two phrases is also interesting as when Mr. Mallard does appear, Louise Mallard is fatally killed.
The first line that pops into my head right now is the very ending line, the one where the doctor proclaims that Louise Mallard had died "of joy that kills." That line is loaded with meaning and irony. First of all, there is the fact that the doctor, and everyone else, just assumed that Louise had been so happy to see her husband that she had died of a heart attack from the joy of it. As we know from earlier in the story, that is not true; in fact, she was dismayed and dealing with her new-found freedom being torn away from her. Secondly, it is interesting how her sister had been so careful to tell her the news of her husband's death, because she was worried that it would shock her. It didn't as much as the opposite, news of her husband. That was the shock that did in her heart.
Another sentence that is important:
There would be no powerful will bending hers in that blind persistence with which men and women believe they have a right to impose a private will upon a fellow-creature.
That line relays Chopin's, and Louise's, view of marriage, that it was someone forcing their will upon another person. That explains Louise's reaction to her husband's death. Another important phrase is when Louise declares, "Free! Body and soul free!" This reveals her joy at being released from marriage. I also like the description of her face as having "repression and even a certain strength." That tells us a lot about her, that she feels repressed, and is a strong woman. One last line is the ever-important intro. to her heart problem, "Knowing that Mrs. Mallard was afflicted with a heart problem" that is at the very beginning of the story.
I hope that those help a bit; good luck!