Nun in sura 19

What is role of Nun in sura 19?

Sometime ago that i was reading sura 19,I saw the verse 19:9. The word that was strange in it was word LamTaku (لم تك).GOD in this verse has used LamTaku instead of LamTakon (لم تكن) . GOD in this place has removed one Noon from the word.GOD in another verse (19:20) in sura 19 has used the same phenomena.GOD almighty has used LamAku (لم اك) instead of LamAkon (لم اكن).

Maybe someone ask what is aim of GOD from these symbols?

When we have receivied these words throughout history very accurate. Therefore we must get good result that this quran that is under hand is main Quran 99.99999 percent . because if this symbols arn't from GOD ; from where writters of quran knew that must write these words without Noon !!!

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