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to follow (someone); to shadow; to tail; to stalk
怪しい男が私をつけている気がする。
I feel like a suspicious man is following me.
犯人を尾けて居場所を突き止めた。
I tailed the suspect and pinpointed their location.
気づかれないようにずっと遠くからそっと尾けた。
I quietly followed from far away the whole time so as not to be noticed.