Complex sentence: Fatimid/Bohra/Dawoodi Bohra believe the same but for their 21st Tayyib, whereas Sunnis believe the future Mahdi has not yet arrived on Earth.
Split into simpler sentences: Fatimid/Bohra/Dawoodi Bohra believe the same but for their 21st Tayyib. Whereas Sunnis believe the future Mahdi has not yet arrived on Earth.