This is the 1849th most frequent Japanese word.
早
"早" means "early" or "fast."
In this sentence, the word '早く' (hayaku) functions as an adverb to describe the action of waking up, indicating the time occurrence as early.
彼は早く起きました。
He woke up early.
Here, '早く' (hayaku) is used as an adverb expressing the expectation for the action to conclude swiftly or sooner than usual, implying hastened completion.
この仕事は早く終わりますか？
Will this work be finished soon?
In this instance, '早い' (hayai) is an adjective describing the nature of growth, emphasizing its promptness or speed.