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intently; single-mindedly; devotedly; solely; earnestly; with all one's heart
彼はひたすら努力を続けてきたのだ。
He has been putting in effort intently.
試験に向けてひたすら勉強している。
I'm studying intently for the exam.
ひたすら謝り続けるしかなかった。
I had no choice but to keep apologizing intently.