Sura 78 An-Naba' (The Announcement), ayah 5

1. ثُمَّ كَلَّا سَيَعْلَمُونَ

   Translation by words

   ثُمَّ

   Then

   كَلَّا

   Nay!

   سَيَعْلَمُونَ

   (soon) they will know.

   Then, no! They are going to know.

   78:5

Translation: Saheeh International