I'rab is the feature of Arabic that most surprises English speakers: the same word turns up with three different endings in three sentences, yet all three translate identically. It is not an arbitrary complication — it is how Arabic shows the role each word is playing, the very job English does with word order. Every ism sits in one of three states: rafa' (the raised case), nasb (the straight case), or jarr (the dragged case), and its role in the sentence decides which. Once you see that, word-endings stop being an obstacle and become a window into the structure of the Qur'an.

From the free course The Language of Quran — Easier than English (Book 1) (LoQ1), taught by Ustad Muhammad Arjan Ali.