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to think constantly about; to dwell on
彼女は亡き父を思い続けた。
She kept thinking about her late father.
彼は過ちを思い続けて、前に進めなかった。
Constantly dwelling on his mistake, he couldn't move forward.
もう会えない人を思い続けるのは、心につらい。
To keep thinking about someone you can never meet again is painful.