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red; crimson; scarlet
red-containing colour (e.g. brown, pink, orange)
red light (traffic)
red ink (i.e. in finance or proof-reading); (in) the red
complete; total; perfect; obvious
Red (i.e. communist)
copper
red 5-point card
秋になると葉が赤に変わる。
In autumn, the leaves turn red.
赤は目立つからよく使われる。
Red stands out so it's often used.
赤と白の組み合わせがとても華やかだ。
The combination of red and white is very gorgeous.