"Rusio estas la plej granda lando."

Translation: Russia is the largest country.

[TheDevLee]

As Duolingo cleverly intends, I learned what "plej" means here by context. It means "most", but is it an adjective? If it is part of the object of a sentence, other than an "esti" sentence, the type used here, does it become plejn?

[tvindy]

I think it's an adverb, since it modifies an adjective.

[Ellenspeaking]

vera demando: kio estas pli bona: ruslando aŭ rusio?

[Esperanta-kato]

Rusujo.

[Ruslan_I]

Ruslando estas mi

[Pethanise]

Ruslano el Ruslando (:

[TobyBartels]

Rusio nun provas fariĝi plej granda.