Unu amiko estas vegetarano.

Unu literally means one, but it can also mean a certain one / one particular.

So in Unu amiko estas vegetarano, the idea is often:

• One friend is a vegetarian
• or A certain friend is a vegetarian

This is a little stronger or more specific than plain English a friend. It suggests one friend out of a group, or one particular friend the speaker has in mind.

Esperanto has no indefinite article. In other words, there is no normal word that simply means English a/an.

Esperanto has:

• la = the
• nothing at all for a/an

So:

• amiko can mean friend or a friend, depending on context
• vegetarano can mean vegetarian or a vegetarian, depending on context

Because of that, unu is not just the normal equivalent of English a. It adds the sense of one or a certain one.

Because -o is the normal noun ending in Esperanto.

• amik- = the root for friend
• amiko = friend
• vegetaran- = the root for vegetarian
• vegetarano = vegetarian (person)

This is one of the most basic patterns in Esperanto:

• -o = noun
• -a = adjective
• -e = adverb
• -i = infinitive verb

So both words end in -o because both are nouns.

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

So estas means:

• am
• is
• are

depending on the subject.

A very important point for English speakers: Esperanto verbs do not change according to person.

So you get:

• mi estas = I am
• vi estas = you are
• li estas = he is
• ŝi estas = she is
• ili estas = they are

It is always estas in the present tense.

Because there is no direct object here.

The -n ending usually marks the direct object. But in this sentence:

• Unu amiko is the subject
• vegetarano is a predicate noun after estas

After esti (to be), Esperanto normally does not use -n on the predicate noun.

So:

• Unu amiko estas vegetarano = correct

not:

• Unu amiko estas vegetarano-n = incorrect

In Esperanto, vegetarano means a vegetarian / a vegetarian person. It is a noun.

That is very natural when talking about a person:

• Li estas vegetarano = He is a vegetarian

There is also an adjective:

• vegetara = vegetarian

But vegetara is more commonly used with things such as:

• vegetara manĝo = a vegetarian meal
• vegetara restoracio = a vegetarian restaurant

So for a person, vegetarano is usually the most natural choice.

It is possible in some contexts, but Unu amiko estas vegetarano is usually better if you mean the person is a vegetarian.

Why?

• vegetarano = a vegetarian person
• vegetara = vegetarian as a quality or type

So:

• Li estas vegetarano = He is a vegetarian
• Li manĝas vegetaran manĝon = He eats vegetarian food

English often uses an adjective where Esperanto prefers a noun for people.

Yes, Esperanto word order is fairly flexible, but this sentence uses the most normal and clearest order:

• Unu amiko = subject
• estas = verb
• vegetarano = complement

So Unu amiko estas vegetarano is the standard way to say it.

You can change word order in Esperanto for emphasis, but with a sentence using estas, the usual order is often the easiest and most natural for learners.

A rough pronunciation is:

OO-noo ah-MEE-koh ES-tahs veh-geh-tah-RAH-noh

A few useful pronunciation points:

• Every letter is pronounced clearly.
• g is always hard, like in go, not like in gem.
• Stress in Esperanto is always on the second-to-last syllable.

So the stress is on:

• U-nu
• a-MI-ko
• ES-tas
• ve-ge-ta-RA-no

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