Helping verbs, also known as auxiliary verbs, are words that assist the main verb in a sentence to convey a specific meaning. They help indicate tense, mood, or voice. Common helping verbs include is, are, was, were, have, and will. For example, in the sentence "She is running," the helping verb is helps show that the action is happening now. These verbs work together with main verbs to form verb phrases. For instance, in "They have finished their homework," the helping verb have indicates that the action of finishing is complete. Understanding helping verbs is essential for constructing clear and grammatically correct sentences.