Commentary explaining the meaning of the ayahs. One passage often covers several ayahs, so neighbouring ayahs can show the same text.
English Al-Mukhtasar tafsir for Surah Al-Qalam — Ayah 1
نٓۚ وَٱلۡقَلَمِ وَمَا يَسۡطُرُونَ ١
The discussion on similar letters has already passed in Sūrah Al-Baqarah. Allah takes an oath on the Pen and whatever the people write with their pens.