Learn Hardcore Esperanto: La infano estas sana.

The sentence literally translates to "The child is healthy." Here, La means "the", infano means "child", estas is the present tense of "to be", and sana means "healthy."

What do the endings -o in infano and -a in sana indicate?

In Esperanto, every noun ends with -o and every adjective ends with -a. Thus, infano is clearly identified as a noun, while sana is marked as an adjective. This consistent system helps learners quickly recognize parts of speech.

Does the noun infano specify the gender of the child?

No, infano is a gender-neutral noun that means "child". Esperanto does not mark gender by default. If you need to refer specifically to a female child, you could use infanino; otherwise, infano can refer to a child of any gender.

What is the function and tense of the verb estas in this sentence?

Estas is the present tense form of the verb esti (to be). It acts as a linking verb or copula, connecting the subject (la infano) with the predicate adjective (sana) to express that the child is healthy in the present time.

How should the words in this sentence be pronounced in terms of stress?

In Esperanto, every word is stressed on the penultimate (second-to-last) syllable. Therefore, infano is pronounced as in-FA-no (with "FA" receiving the stress) and sana as SA-na. This regular stress pattern greatly simplifies pronunciation.