zhè zhǒng / qīng jié jì de / zhǔ yào chéng fèn / shì / cǎo suān / néng qù chú / wán gù wū zì这种清洁剂的主要成分是草酸,能去除顽固污渍。The main ingredient in this cleaner is oxalic acid, which can remove stubborn stains.