Idgham [Assimilation] If a Sakin [ ن ] or Tanwin precedes [ و ] or [ ي ], the [ ن ] and Tanwin will be assimilated into the following [ و ] or [ ي ]. Notice that [ و ] and [ ي ] will be doubled and uttered with a Ghunnah [nasal twang]. As explained in previous lesson, if a Sakin [ ن ] or Tanwin precedes a [ ن ] or [ م ], the [ ن ] and Tanwin will be assimilated into the following [ ن ] or [ م ] Though [ و ] and [ ي ] are pronounced with Tashdid [Doubling], no Shaddah sign [ ّ ] is written over them in the `Uthmanic calligraphy of the Qur"an.