Nouns ending in y preceded by a vowel form their plurals by adding -s.

What is the difference between theme and universal theme? theme refers to the central insight revealed through an american story, while universal theme refers to a theme revealed through a story of foreign origin. theme refers to a central message that applies to anyone, anywhere, while universal theme is particular to a certain individual, historical context, or culture. theme refers to the central insight revealed through a story, while universal theme refers to a theme that applies to anyone, anywhere. theme and universal theme are two terms that have the same definition.