Tadʿu is the jussive of tadʿū (its weak final wāw is deleted); yastajib is jussive with sukūn. The conditional response has a different jussive sign.
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In with a Weak Final Verb
Conditional Particles: In, Law and Ammā
Tadʿu is the jussive of tadʿū (its weak final wāw is deleted); yastajib is jussive with sukūn. The conditional response has a different jussive sign.