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one face; one surface
the whole surface
one aspect; one side
(on) the other hand
one broad, flat object
front page (e.g. newspaper)
田んぼが1面に広がる風景が車窓から見えた。
A landscape of rice paddies stretching across the entire area was visible from the train window.
彼の性格には大胆な1面と繊細な1面がある。
His personality has both a bold side and a delicate side.
新聞の1面にその事件が大きく取り上げられた。
The incident was prominently featured on the front page of the newspaper.