La tigo estas longa.

La is the Esperanto definite article, the equivalent of the.

Esperanto has:

• la = the
• no separate word for a/an

So:

• la tigo = the stem
• tigo by itself can mean a stem or just stem, depending on context

That often feels unusual to English speakers at first, because English requires a/an in many places where Esperanto simply uses the noun alone.

In Esperanto, nouns normally end in -o.

So tigo is clearly a noun because of the -o ending. This is one of the most regular features of Esperanto grammar.

Some common endings are:

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

So in this sentence:

• tigo is a noun
• longa is an adjective

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

So estas corresponds to English am / is / are, depending on context.

A very important point: Esperanto verbs do not change form depending on the subject.

So all of these use estas:

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

That makes Esperanto verbs much simpler than English verbs.

Because longa is an adjective, and adjectives in Esperanto end in -a.

Compare:

• longo = length, the noun
• longa = long, the adjective
• longe = longly / at length, the adverb

In this sentence, the word describes the noun tigo, so it must be an adjective:

• La tigo estas longa.

Because it is still describing the noun tigo.

In La tigo estas longa, longa is a predicate adjective: it comes after the verb estas, but it still tells you a quality of tigo.

English does the same thing in structure:

• The stem is long.

In Esperanto, adjectives keep their adjective ending -a whether they come:

• before a noun: la longa tigo
• after esti: la tigo estas longa

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

Here:

• tigo is singular
• it is not accusative
• so the adjective is also singular and not accusative: longa

Examples:

• la longa tigo = the long stem
• la longaj tigoj = the long stems
• mi vidas la longan tigon = I see the long stem

So agreement is very regular:

• singular noun → singular adjective
• plural noun → plural adjective
• accusative noun → accusative adjective too

Because nothing here is in the accusative.

The -n ending in Esperanto is commonly used for:

1. the direct object
2. motion toward something in some expressions

In La tigo estas longa, the sentence uses estas and a predicate adjective. There is no direct object.

So:

• la tigo is the subject
• longa describes the subject
• no accusative is needed

That is why you do not say:

• La tigon estas longa
• La tigo estas longan

Both would be wrong here.

It can be before the noun in Esperanto, but this sentence has a different structure.

Compare these:

• la longa tigo = the long stem
• la tigo estas longa = the stem is long

The first is a noun phrase.
The second is a full sentence with the verb estas.

So longa is not being placed after the noun directly; it is coming after the verb estas.

To some extent, yes. Esperanto word order is fairly flexible, but some orders are more normal than others.

The standard, neutral order is:

• La tigo estas longa.

You may also see:

• Longa estas la tigo.

That is grammatical, but it sounds more emphatic or literary, as if stressing longa.

For a beginner, the safest choice is the normal order:

• subject + verb + complement

A simple pronunciation guide is:

• La → lah
• tigo → TEE-go
• estas → ES-tahs
• longa → LON-gah

A few pronunciation notes:

• Esperanto stress is usually on the second-to-last syllable
• g is always a hard g, as in go
• each vowel is pronounced clearly

So the stress pattern is:

• TI-go
• ES-tas
• LON-ga

Yes. Esperanto verbs do not change according to person or number.

So you always use estas for the present tense of esti:

• mi estas
• vi estas
• la tigo estas
• ili estas

This is different from English, where you must choose among am, is, and are. In Esperanto, one form does the whole job.