You may have said more than once, "I like coffee but I hate tea." These are two simple, almost symmetrical sentences that express your preferences. If we pay attention, we'll see that they don't function the same way. In "I like coffee," the subject is coffee, not "I." The speaker appears as the indirect object: "(coffee) is liked by me." In contrast, in "I hate tea," "I" is the subject, while "tea" is the direct object. They express similar experiences, but with different grammatical structures. Verbs like "to like" and "to hate," as well as "to worry," "to frighten," "to interest," and "to bother," are examples of what linguists call psychological verbs—verbs that express mental or emotional states. They all share the same situation: there is someone who feels an emotion (the experiencer) and something that provokes it (the stimulus or theme). What changes between languages—and even within the same language—is how these two roles are organized in the sentence.