وَٱلْجِبَالَ أَوْتَادًا
Sentence structure
This ayah continues the two-object construction of the preceding ayah. ٱلْجِبَالَ is coordinated with its first object ٱلْأَرْضَ, and أَوْتَادًا corresponds to the second object مِهَـٰدًا.
وَٱلْجِبَالَ — and the mountains
Grammar: وَ is a conjunction and ٱلْ the definite article. جِبَالَ is an accusative broken plural, coordinated with ٱلْأَرْضَ as the first object of the understood continuing verb نَجْعَلِ.
أَوْتَادًۭا — as pegs
Grammar: An indefinite masculine broken plural in the accusative, functioning as the corresponding second object.