Without the word spring in the first sentence of this paragraph, how would you know the time of year in which the story takes place? The following options apply:
-Buds on the trees were swelling.
-The association of youth and gladness with the rebirth symbolized by spring.
The swelling buds point to a specific time in the life cycle of trees while the association of youth and gladness as elements of spring, of the rebirth of spring, is quite strong in this paragraph, specially as “youth and gladness” are located clearly on the sky and earth.
The remaining option, “Branches rustled faintly in the fresh breeze”, doesn’t provide a link to spring as strong as the other options.