جَلَسْتُ جَلْسَةً
Translation: I sat once.
جَلَسْتُ: past verb with subject pronoun.
جَلْسَةً: accusative absolute object specifying one occurrence.
Here the maṣdar counts the action rather than describing its kind.
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Number: One Occurrence
The Accusatives: Al-Mafʿūl al-Muṭlaq
جَلَسْتُ جَلْسَةً
Translation: I sat once.
جَلَسْتُ: past verb with subject pronoun.
جَلْسَةً: accusative absolute object specifying one occurrence.
Here the maṣdar counts the action rather than describing its kind.