Here's why:
* Helping verbs (also called auxiliary verbs) help to form verb tenses and moods. They work with the main verb to create a complete verb phrase.
* "Have" is often used with the past participle of a verb to create the present perfect tense (e.g., "I have eaten", "They have gone"). It can also be used with the past participle to create the present perfect continuous tense (e.g., "I have been working").
Here are some examples of "have" as a helping verb:
* I have been to the store.
* They have finished their homework.
* We have been studying for the test.
Let me know if you have any other questions!