فِى عَمَدٍ مُّمَدَّدَةٍۭ ۝٩ What is the role of مُّمَدَّدَةٍۭ?

Surah Al-Humazah — Part 1

• Genitive adjective of عَمَدٍۢ
• Nominative subject
• Accusative object
• Future particle