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that year; same year; same age
同年の秋に新しい法律が施行された。
In the autumn of that year, a new law was enacted.
彼とは同年の生まれで気が合う。
He and I were born the same year and get along well.
入社は同年だが部署は違う。
We joined the company the same year but are in different departments.