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structural alteration (of a building); reconstruction; rebuilding; remodelling; remodeling
老朽化した校舎を改築する計画がある。
There is a plan to rebuild the aging school building.
改築工事のため一年間仮設校舎を使う。
During the reconstruction, a temporary building will be used for one year.
自宅を改築して二世帯住宅にした。
I rebuilt my home into a two-family house.