Internal stem change can involve the modification of vowels or consonants of the root. This process can occur alone, or in conjunction with affixation.[1]

Umlaut 

Main article: Umlaut

When suffixes that contain a front vowel are added to the stem, the vowel in the stem becomes fronted.

This process can be seen in the kin terms in German[1]:

  • Bruder 'brother' - Brüderlein 'brother-dimin'
  • Frau 'woman' - Fräulein 'woman-dimin'Lederer, Herbert. 1969. Reference Grammar of the German Language. New York: Charles Scribner’s Sons.

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Phillipvl (talk) 06:52, 2 December 2016 (UTC)Phillip