La posteno estas plentempa.

La is the Esperanto definite article, meaning the.

So la posteno means the position / the job. If you said just posteno, it would sound more like a position or simply position in a more general sense.

A useful point: la never changes in Esperanto. It does not have different forms like the, a, an, or gendered articles in some other languages.

Posteno usually means position, post, or job position.

It often refers to a role or employment position rather than the abstract idea of work in general. Depending on context, English might translate it as:

• position
• post
• job

So in this sentence, posteno is talking about the role itself.

Estas is the present-tense form of esti, which means to be.

So:

• mi estas = I am
• ĝi estas = it is
• la posteno estas = the position is

Esperanto verbs do not change for person or number, so estas is always the same whether the subject is singular or plural:

• la posteno estas
• la postenoj estas

Both use estas.

The ending -a marks an adjective in Esperanto.

Since plentempa describes posteno, it has to be an adjective:

• posteno = a noun
• plentempa = an adjective describing that noun

So the structure is:

• La posteno = the position
• estas plentempa = is full-time

In Esperanto, adjectives usually end in -a.

Plentempa is a compound adjective meaning full-time.

It is built from the idea of:

• plen- = full
• temp- = time
• -a = adjective ending

So plentempa literally means something like full-time-related or of full time.

If you said plena tempo, that would mean full time as a noun phrase, not an adjective describing the job. But here we need an adjective because we are describing the position.

Compare:

• plentempa posteno = a full-time position
• plena tempo = full time

There is no -n because plentempa is not a direct object here.

In La posteno estas plentempa, the word plentempa is a predicate adjective after estas. Predicate adjectives normally do not take -n.

So:

• Mi vidas la plentempan postenon. = Here plentempan describes a direct object, so it gets -n.
• La posteno estas plentempa. = Here it comes after estas, so no -n.

You may sometimes see hyphens in compounds, especially if a writer wants to make the structure extra clear, but standard Esperanto normally prefers writing such compounds as one word: plentempa.

So the usual form is:

• plentempa

not:

• plen-tempa

Writing it as one word is the most natural choice.

Yes. In Esperanto, adjectives agree with the nouns they describe in number and case.

Here:

• posteno is singular
• it is not accusative
• so the adjective stays singular and without -n

That gives:

• La posteno estas plentempa.

If the noun were plural, the adjective would also become plural:

• La postenoj estas plentempaj. = The positions are full-time.

The normal word order is very similar to English:

• La posteno = subject
• estas = verb
• plentempa = predicate adjective

So La posteno estas plentempa is the most neutral and natural order.

Esperanto does allow some flexibility, but this is the standard beginner-friendly pattern.

A simple pronunciation guide is:

la pos-TE-no ES-tas plen-TEM-pa

A few helpful points:

• stress in Esperanto normally falls on the second-to-last syllable
• posteno → pos-TE-no
• estas → ES-tas
• plentempa → plen-TEM-pa

That regular stress pattern is one of the nice things about Esperanto.