Answer:
have
Step-by-step explanation:
It is the verb that is not the action of the sentence. Is the sentence about having or studying?
Here is another way to tell -
Think of the helping verb jingle (to the tune of jingle bells):
Helping verbs, helping verbs, there are 23:
Am, is, are, was and were, being, been, and be, oh!
Have, has, had, do, does, did, shall, will, sohuld, and could!
There are five more helping verbs: may, might, must, can, could!