Answer:
Quickly.
Step-by-step explanation:
Adverb is a word that is used to describe a verb, or an action.
For example, the word "passed" is a verb, because it is an action you do, for example: I passed you on the way to my next class in the hallway.
In this case, "quickly" is used to help describe "passed", and to give a reader a sense of the speed in which the school year passed.
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