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dilute
rare
Greece
稀塩酸を使って実験した。
We experimented using dilute hydrochloric acid.
こんな珍しい鳥を見るのは稀なことだと思う。
I think it's rare to see such an unusual bird.
稀硫酸の濃度を正確に測定する必要がある。
The concentration of the dilute sulfuric acid needs to be measured accurately.