In English, "yes" is the most common way to say "yes" in oral communication. However, there are many other ways to express agreement in English, such as "certainly," "absolutely," "definitely," "indeed," "of course," and "agreed." It's also common to simply nod your head or give a thumbs up to indicate agreement. It's important to choose the right word or gesture depending on the context and the degree of agreement you want to express.
