Surah Al-Kahf Ayah #104 Translated in English
الَّذِينَ ضَلَّ سَعْيُهُمْ فِي الْحَيَاةِ الدُّنْيَا وَهُمْ يَحْسَبُونَ أَنَّهُمْ يُحْسِنُونَ صُنْعًا
[They are] those whose effort is lost in worldly life, while they think that they are doing well in work."