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• Russian
  у́зкийuzkij

  ˈuskʲɪjinherited
• Ukrainian
  вузьки́йvuzʹkyj

  ʋuzʲˈkɪjinherited

  Ukrainian adds a prothetic в- before the initial u.

• Polish
  wąski

  ˈvɔ̃skʲiinherited

  Polish keeps the nasal vowel and adds a w- in front.

• Czech
  úzký

  ˈuːskiːinherited
• Bosnian-Croatian-Serbian
  uzakузак

  ˈuzakinherited
• English
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Sound laws at work

• Nasal vowels (ę, ǫ)
• The fall of the yers