"The good boys are sleeping."

Translation: Sȳri taobi ēdrusi.

[JayantJeet]

Why are we not using syz?

[Ctxkh1Me]

Sȳri is the plural form. Adjectives have to agree in gender, case, and number with the nouns they modify. Thus you have sȳz taoba and sȳri taobi.

https://wiki.dothraki.org/High_Valyrian_Adjectives#S.C8.B3z-type