The connecting hamza of al-ṣalātu drops in continuous pronunciation. The feminine tāʾ takes kasra to avoid two consecutive sukūns; this is liaison rather than a change in pronoun identity.
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Why the Kasra Appears
Feminine Tāʾ in the Past Tense: Form and Agreement
The connecting hamza of al-ṣalātu drops in continuous pronunciation. The feminine tāʾ takes kasra to avoid two consecutive sukūns; this is liaison rather than a change in pronoun identity.