La arkitekto montras la skizon al la reprezentanto.

Because la skizon is the direct object of the verb montras.

In Esperanto, the direct object usually takes the accusative ending -n:

• la skizo = the sketch
• la skizon = the sketch (as the thing being shown)

By contrast, al la reprezentanto means to the representative. The word al already shows that this noun is an indirect object / direction of giving or showing, so reprezentanto does not need -n here.

So:

• montras la skizon = shows the sketch
• al la reprezentanto = to the representative

Al means to. It marks the person who receives the action.

In this sentence:

• the architect is doing the showing
• the sketch is what is being shown
• the representative is the person to whom it is shown

So al la reprezentanto = to the representative.

This is very common in Esperanto with verbs like:

• doni = to give
• sendi = to send
• montri = to show

For example:

• Mi donas la libron al ŝi. = I give the book to her.
• Li montras la planon al la kliento. = He shows the plan to the client.

Normally, no. In a sentence like this, al is the standard and clearest way to mark the recipient.

So you say:

• La arkitekto montras la skizon al la reprezentanto.

Using -n on both nouns would be confusing, because -n usually marks the direct object, not the recipient.

Esperanto strongly prefers:

• direct object → -n
• recipient / person something is given or shown to → al

La means the.

Esperanto has just one definite article:

• la = the

It does not change for:

• singular or plural
• masculine or feminine
• case

So all three noun phrases use the same article:

• la arkitekto = the architect
• la skizon = the sketch
• la reprezentanto = the representative

English also uses the repeatedly in similar sentences, so this part is quite straightforward.

Montras is the present tense form of montri.

In Esperanto:

• -i = infinitive
• -as = present tense
• -is = past tense
• -os = future tense

So:

• montri = to show
• montras = shows / is showing

That means:

• La arkitekto montras la skizon... = The architect shows / is showing the sketch...

Esperanto present tense often covers both simple present and present progressive, depending on context.

Not as rigidly as in English.

Because Esperanto marks the direct object with -n, the sentence can allow more flexibility in word order without losing the basic meaning.

The neutral order is:

• La arkitekto montras la skizon al la reprezentanto.

But other orders are also possible for emphasis, for example:

• La skizon la arkitekto montras al la reprezentanto.
• Al la reprezentanto la arkitekto montras la skizon.

Even so, the most natural order for learners is usually: subject + verb + object + al-phrase

So the given sentence is the standard, clear version.

In Esperanto, nouns usually end in -o.

So:

• arkitekto = architect
• skizo = sketch
• reprezentanto = representative

This is one of the most helpful features of Esperanto: word endings show word class clearly.

Here:

• -o marks nouns
• -as marks the verb
• -n marks the direct object

That makes the structure easy to identify.

Reprezentanto can be broken down like this:

• reprezent- = represent
• -ant- = active participant, someone doing the action
• -o = noun

So reprezentanto literally means someone who represents.

This -ant- ending is useful in many words:

• parolanto = speaker
• lernanto = learner/student
• helpanto = helper

So reprezentanto is a very regular Esperanto formation.

A simple pronunciation guide is:

ski-zon

More exactly:

• sk as in English স্ক? Better to think of sk in skin
• i like ee in see
• z like z in zoo
• o like o in a pure vowel sound, not a diphthong
• n as usual

Stress in Esperanto normally falls on the second-to-last syllable, so:

• SKI-zon

The base form skizo is stressed the same way:

• SKI-zo

Because la never changes.

Unlike in some languages, Esperanto’s definite article stays the same in all situations:

• la skizo
• la skizon
• la skizoj
• la skizojn

The noun changes, but the article does not.

So in this sentence:

• la stays la
• skizo becomes skizon because it is the direct object

Yes.

Esperanto -as does not force a difference between:

• shows
• is showing

Both can be translated by montras, depending on context.

So:

• La arkitekto montras la skizon al la reprezentanto. could mean either:
• The architect shows the sketch to the representative.
• The architect is showing the sketch to the representative.

If you need to make the timing especially clear, context usually does the job.