لِّلطَّـٰغِينَ مَـَٔابًا
Sentence structure
This ayah completes the preceding description of Hell. لِّلطَّـٰغِينَ specifies for whom it lies in wait, while مَـَٔابًا is another predicate of the preceding كَانَتْ: a place of return for the transgressors.
لِّلطَّـٰغِينَ — for the transgressors
Grammar: لِـ is a preposition. ٱلطَّـٰغِينَ is a definite sound masculine plural made genitive with يَاء; the phrase is linked to the preceding كَانَتْ.
مَـَٔابًۭا — a place of return
Grammar: An indefinite accusative masculine noun functioning as another predicate of the preceding كَانَتْ. It is a noun of place from the root أ و ب.