Which word in this sentence is an adverb? the brave firefighters raced quickly toward the abandoned warehouse.
a. brave
b. quickly
c. toward
d. abandoned

An adverb is something that modifies an adjective or verb.
Brave is an adjective since it describes a noun.
Toward is also an adjective since it describes where the firefighters were going.
Abandoned is an adjective since it describes the warehouse.
The adverb is quickly, which describes the verb, raced.
So the answer is B. quickly.