This is the 169th most frequent German word.
schnell
Fast.
In this sentence, 'schnelle' is used as an adjective describing the noun 'Läufer' (runner), highlighting their speed.
Der schnelle Läufer gewann das Rennen.
The fast runner won the race.
'Schnell' functions as an adverb here, modifying the verb phrase 'meine Hausaufgaben machen' to indicate swiftness in completion.
Ich muss schnell meine Hausaufgaben machen.
I have to quickly do my homework.
Here, 'schnell' is an adverb describing how the car drives, emphasizing the speed of the action.