Основні випадки чергування [у] - [в], [і] - [й] (правила милозвучності).

https://lms.e-school.net.ua/asset-v1:UIED+Geometry-11th-grade+2020+type@asset+block@asset-v1_UIED_Ukrainian-language-10th-grade_2020_type_asset_block_%D1%83%D0%BA%D1%80%D0%BC%D0%BE%D0%B2%D0%B010_24__1_.pdf
https://www.canva.com/
file:///C:/Users/Lenovo/Downloads/asset-v1_UIED+UM-NUSH-5-6th+2022+type@asset+block@%D0%9C%D0%B8%D0%BB%D0%BE%D0%B7%D0%B2%D1%83%D1%87%D0%BD%D1%96%D1%81%D1%82%D1%8C_%D1%83%D0%BA%D1%80%D0%B0%D1%97%D0%BD%D1%81%D1%8C%D0%BA%D0%BE%D1%97_%D0%BC%D0%BE%D0%B2%D0%B8._%D0%9E%D1%81%D0%BD%D0%BE%D0%B2%D0%BD%D1%96_%D0%B2%D0%B8%D0%BF%D0%B0%D0%B4%D0%BA%D0%B8_%D1%87%D0%B5%D1%80%D0%B3%D1%83%D0%B2%D0%B0%D0%BD%D0%BD%D1%8F._%D0%9A%D0%BE%D0%BD%D1%81%D0%BF%D0%B5%D0%BA%D1%82__204000__%D0%B2%D1%96%D0%B2%D1%82%D0%BE%D1%80%D0%BE%D0%BA_09__%D0%BA%D0%B2%D1%96%D1%82%D0%B5%D0%BD%D1%8C_2024_.pdf
https://www.miyklas.com.ua/p/ukrainska-mova/5-klas/fonetika-grafika-orfoepiia-orfografiia-14565/osnovni-vipadki-cherguvannia-u-v-i-i-z-iz-zi-pravila-milozvuchnosti-41612/re-d364a2bb-49b4-46ff-bae0-b37890ad88fe
https://naurok.com.ua/osnovni-vipadki-cherguvannya-u-v-i-y-z-zi-iz-89298.html
https://naurok.com.ua/vpravi-na-cherguvannya-u-v-i-y-iz-z-zi-18609.html