When the -ing form of a verb is used as the main verb of the predicate, the auxiliary must contain a form of <u>be</u>.
<h3>What is a verb?</h3>
It should be noted that a verb simply means a action word that's used to illustrate that something has occured.
In this case, when the -ing form of a verb is used as the main verb of the predicate, the auxiliary must contain a form of be.
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C is your answer im pretty sure
