no it is a main verb
Verb have is the helping verb sold is the action verb
it is verb
It's a verb, a compound verb made from the infinitive stem "be" and the auxiliary "can". In addition, "Can be" can be a helping verb phrase, e.g. "Tom can be helping the younger kids". Can be is helping the verb helping.
"Do" is a verb when used in a question as a helping verb helping to form the interrogative structure.
Yes it is because it is part of a verb
"Has started" is a verb phrase. "Has" is the helping verb (auxiliary verb) and "started" is the main verb.
In this case, will is an auxiliary verb, which is the grammatical term for a 'helping' verb.
'helping verb - or auxiliary verb
The word been is a verb. It is the past participle of the verb to be.
Sold is a verb. It's the past tense of sell.
Is gaining is a verb, consisting of a helping verb is plus a present participle gaining.
Will can be a few different parts of speech. Will, as in "I will play that game later." is a helping verb, or an auxillairy verb. Will, as in "She was stated in her grandmother's will." is a noun. Will, as in "It was his will." is also a noun. Will, as in "He willed it to happen." is a verb.