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dilute
rare
Greece
希代の天才と称えられた科学者がいた。
There was a scientist praised as a once-in-a-generation genius.
希少な資源を大切に使わなければならない。
We must use rare resources carefully.
希塩酸は強酸を水で薄めて作る。
Dilute hydrochloric acid is made by diluting a strong acid with water.