〜ことなく koto naku
〜ことなく（koto naku）means “without (doing); never (doing)”. A formal, written equivalent of 〜ないで／〜ずに, meaning an action is done without the other action ever occurring. Formation: V-る（辞書形）＋ことなく
without (doing); never (doing)
N2Formation
V-る（辞書形）＋ことなく
Explanation
A formal, written equivalent of 〜ないで／〜ずに, meaning an action is done without the other action ever occurring. Often stresses continuity or 'not even once.'
Examples
彼は一日も休むことなく働き続けた。
かれはいちにちもやすむことなくはたらきつづけた。
He kept working without taking even a single day off.
その夢をあきらめることなく、ついに実現させた。
そのゆめをあきらめることなく、ついにじつげんさせた。
Without ever giving up on that dream, he finally made it come true.
Note
Written/formal; in everyday speech use 〜ないで or 〜ずに.
FAQ
〜ことなく — what does it mean and how is it used?
without (doing); never (doing). A formal, written equivalent of 〜ないで／〜ずに, meaning an action is done without the other action ever occurring. Often stresses continuity or 'not even once.'
〜ことなく — how do you form it?
V-る（辞書形）＋ことなく
〜ことなく — any usage notes?
Written/formal; in everyday speech use 〜ないで or 〜ずに.