18:104
اَلَّذٖینَ ضَلَّ سَعْیُهُمْ فِی الْحَیٰوةِ الدُّنْیَا وَهُمْ یَحْسَبُونَ اَنَّهُمْ یُحْسِنُونَ صُنْعًا
Allatheena dalla saAAyuhum fee alhayati alddunya wahum yahsaboona annahum yuhsinoona sunAAan
Translations
[They are] those whose effort is lost in worldly life, while they think that they are doing well in work
Saheeh International
Those whose effort goeth astray in the life of the world, and yet they reckon that they do good work
Marmaduke Pickthall