it is the use of the verb's noun after the verb. for example: i played ( playing) ( انا لعبت (لعبا i won (winning) ( انا فزت (فوزا

هُوَ مَصْدَرٌ يُذْكَرُ بِعْدَ فِعْلِ صَرِيحٍ من لَفْظِهِ مِنْ أَجْلِ تَوْكِيدِ مَعْنَاهُ أو بِيَانِ عَدَدهِ ، أَوْ بَيَانِ نَوْعِهِ ، أَوْ بَدَلاُ من إِعَادَةِ ذِكْرِ الفِعْلِ. It's a gerund form comes after a frank verb to confirm / emphasis it's meaning, numbering, kind or instead of repeating the verb. It comes after a frank verb [only infinitive], from it's origin letters. i.e شرب شربا - ضرب ضربا - عمل عملا - أكل أكلا - نام نوما etc. Or, it may come after a vicar verb [which is acting -on behalf of- the infinitive] . This include so many cases. i.e وقفت قيامًا - توضأ المصلي وضوءًا - اجتهدت أحسن الاجتهاد - جلس الولد القرفصاء - أنذرت الحارس ثلاثًا For more explanation visit the following link. http://www.schoolarabia.net/arabic/maf3ol_motlak/maf3ol_motlak1.htm I can help with any further indications.

I believe it is when you use the verb in a sentence a second time using the gerund form as an adverb. It is stylisticly Arabic and occurs quite often in classical Arabic.

I'm a native arabic speaker

i still cannot differentiate between maf'ul muthlaq and masdar? :)