A main verb can stand by itself as the simple predicate of a sentence while the helping verb cannot.
A helping verb (also called an auxiliary verb) is a verb that is used together with the main verb of the sentence to convey the action, so it helps the verb be more precise. The helping verb will often be a form of the verb (to be), or the verb (to have) or the verb (will) to show action in the future. When there is a helping verb, the main verb is often a gerund (a form of the verb that ends in –ing) or a past participle (a form of the verb which often ends in –ed, –n, or–en).
On the other hand, the linking verb is a verb that connects the subject with an adjective or a noun that describes it.
Example: Anna got mad (the linking verb got connects the subject Anna with the adjective mad.
The student has been writing essays all day. (Helping verb: has been; Main verb: writing)
Amanda may run in the park. (Helping verb: may; Main verb: run)
The man has gone. (Helping Verb: has; Main verb: gone)
Did you throw it? (Helping Verb: did; Main Verb: throw)
Be Am Is Are Was Were Being Been
Have Has Had Do Does Did May Might
Must Can Could Shall Will Should Ought Would
