例句：

　　The very thought of it makes me feel sick. （用作形容詞）

　　一想到這事就使我惡心。

　　I took her classes for her while she was sick. （用作形容詞）

　　她生病時我為她代課。

　　The sick need special care. （用作名詞）

　　病人需要特別護(hù)理。