► 形容動詞不純  [ふじゅん]    
meaning:  pure  rank: 3☆ この
金属には不純物が
混じっている ⇨ This metal contains impurities
不純  [ふじゅん]    
meaning:  sincere  rank: 3☆ 
彼の
動機は不純だ ⇨ His motive is not pure. He has an ulterior motive
More examples:- 不純物が薬品に混入した ⇨ Impurity were introduced into the chemical solution