Attached pronouns (الضمائر المتصلة) are suffixes added to the end of nouns, verbs, and particles to indicate possession, direct objects, or the objects of prepositions. They are one of the most frequently used grammatical elements in Arabic, appearing in virtually every sentence.
When attached to nouns, they indicate possession: كتابي (my book), كتابُك (your book), كتابُه (his book), كتابُها (her book), كتابُهم (their book). The attached pronoun replaces the tanween and makes the noun definite through the إضافة (possessive) construction. This is one of the ways a word can become معرفة (definite) without using ال.
When attached to verbs, they serve as direct objects: رأيتُهُ (I saw him), سمعتُها (I heard her), أعطاني (he gave me). The pronoun is in the محل نصب (accusative position) because it functions as the مفعول به (direct object). Learning to quickly identify attached pronouns on verbs is essential for understanding Arabic sentences.
When attached to particles and prepositions, they serve as the objects of those particles: لهُ (for him), بها (with it/her), عليكم (upon you all), فيه (in it/him). Prepositions always require their objects to be in the مجرور (genitive) case, and attached pronouns after prepositions are accordingly in محل جر.
The full set of attached pronouns covers all persons, genders, and numbers. Memorizing them and recognizing them instantly is a fundamental skill that the Ilm Al Lughah Nahw courses build systematically through lessons, quizzes, and flashcard drills. Once you master attached pronouns, you'll find Arabic text much easier to parse and understand.