Learn Hardcore Esperanto: La libro estas utila por lerni Esperanton. - The book is useful for learning Esperanto.

Por translates as “for” and is used here to indicate purpose. In the sentence, it shows that the book is useful for the purpose of learning Esperanto.

Why does Esperanton end with -n instead of just Esperanto?

In Esperanto, the direct object of a verb takes an accusative ending, which is -n. Since Esperanton is the thing being learned (the direct object of lerni), it receives the -n to mark its role.

What do the word endings -o, -a, and -i in this sentence indicate?

Each ending in Esperanto signals the part of speech: • -o (in libro) marks a noun. • -a (in utila) marks an adjective. • -i (in lerni) denotes the infinitive form of a verb. These endings help clearly identify each word’s grammatical role.

Why is lerni in its base (infinitive) form and how does it function in the sentence?

Lerni is the infinitive form of the verb “to learn.” In this context, it explains the purpose of the book. It is used after por to indicate that the book is intended for learning Esperanto.

Is the use of the definite article la before libro necessary?

Yes, la is the definite article meaning “the.” It specifies that we are referring to a particular book. In Esperanto, as in English, using la helps clarify which book is being discussed.