Full Explanation, with Examples and Brain Friendly Flashcards.
The Arabic language is a very logical language, where the grammatical case of the word affects its ending. Grammatical case signifies where the word is placed in the sentence; for example: is it the subject or object?; and whether it is affected by the case of a governing particle; for example: a noun after a proposition (Harf AL-Jarr) will always be in the genitive case and have a Kasra ending .
أكَلَ الوَلَدُ التُّفَّاحَةَ.
The boy ate the apple.
the boy = الوَلَدُ the doer/ who did the verb or action الفاعل "Faa'il"
Being a "doer", "the boy" will be in the nominative case and take a Damma diacritic, which is a nominative sign.
the apple = التُّفَّاحَةَ the object of the verb / the thing or one that received the action or was affected by it.
Being the object, "the apple" will be in the accusative case and take a FatHa diacritic, which is an accusative sign.
أنا في البَيْتِ.
I am at home.
Here, "home" البيت is after "at" في, which is a paricle of Jarr or preposition, causing البيت noun to be in the genitive case and take a Kasra ending, a gentive sign.
*Note: A diptote noun will take FatHa instead of Kasra; so the FatHa becomes the deputy of Kasra in the genitive case. Example:
سَلَّمْتُ على عُمَرَ.
I said hello to Omar.
(Omara) with FatHa and not (Omarin).
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