La gasto demandas, ĉu la mapo montras la plej mallongan vojon al la biblioteko.

The guest asks whether the map shows the shortest way to the library.

Breakdown of La gasto demandas, ĉu la mapo montras la plej mallongan vojon al la biblioteko.

• la: the
• al: to
• demandi: to ask
• montri: to show
• mallonga: short
• plej: most
• biblioteko: the library
• gasto: the guest
• mapo: the map
• vojo: the way
• ĉu: whether

Questions & Answers about La gasto demandas, ĉu la mapo montras la plej mallongan vojon al la biblioteko.

What exactly does ĉu do in this sentence?

Ĉu introduces a yes–no question (a question whose answer is “yes” or “no”).

In a direct question:

• Ĉu la mapo montras la plej mallongan vojon? – Does the map show the shortest way?

In your sentence, the question is indirect (embedded under demandas “asks”), so ĉu still marks that what follows is a yes–no question:

• La gasto demandas, ĉu… – The guest asks whether…

So: ĉu here = whether / if (in the sense of a yes–no question).

Why is there a comma before ĉu?

Esperanto normally uses a comma to separate a main clause from a following subordinate clause:

• Main clause: La gasto demandas
• Subordinate clause (indirect question): ĉu la mapo montras la plej mallongan vojon al la biblioteko

The comma is similar to English:

• The guest asks, whether the map shows…

So the comma marks the boundary between what the guest does (asks) and what exactly is being asked (the clause introduced by ĉu).

Could I use se instead of ĉu, like …demandas, se la mapo montras…?

No. Se means “if (on condition that)”, not “whether”.

• ĉu = whether / if (yes–no question)
  • Mi ne scias, ĉu li venos. – I don’t know whether he will come.
• se = if (condition)
  • Mi iros, se li venos. – I will go if he comes.

In your sentence we have a question (“Does the map show…?”), so only ĉu is correct:

• La gasto demandas, ĉu la mapo montras… – The guest asks whether the map shows…

What part of speech is ĉu?

Ĉu is a question particle.

• It doesn’t change form.
• It doesn’t take plural or tense endings.
• It simply marks that the following clause is a yes–no question.

In direct questions it usually goes at the start:

• Ĉu vi komprenas? – Do you understand?

In indirect questions it introduces the embedded clause:

• Mi demandas, ĉu vi komprenas. – I ask whether you understand.

Why is it demandas, ĉu… and not something like demandas, ke…?

Ke introduces a clause that simply states a fact, not a yes–no question.

• Mi scias, ke la mapo montras la plej mallongan vojon.
  I know that the map shows the shortest way. (statement)

• Mi demandas, ĉu la mapo montras la plej mallongan vojon.
  I ask whether the map shows the shortest way. (question)

So:

• Use ke = that when the content is a statement.
• Use ĉu = whether when the content is a yes–no question.

Why is it montras and not montri after demandas?

Because ĉu la mapo montras la plej mallongan vojon al la biblioteko is a full clause, not an infinitive phrase.

Compare:

• Li demandas, ĉu la mapo montras…
  He asks whether the map shows… – the verb montras is a normal finite verb (present tense).
• Li petas montri la mapon.
  He asks (someone) to show the map. – here montri is an infinitive (“to show”).

Your sentence is not “asks to show”, but “asks whether [it] shows”, so you need a complete clause with a conjugated verb: montras.

What tense is montras, and why not montris or montros?

Montras is the present tense of montri (“to show”).

It describes something that is true now (or generally true at the relevant time):

• La mapo montras… – The map shows… (in general / at this moment)

You could use other tenses if the context changes:

• …ĉu la mapo montris la plej mallongan vojon… – whether the map showed… (in the past)
• …ĉu la mapo montros la plej mallongan vojon… – whether the map will show… (in the future)

In the given sentence, the natural reading is that the map currently shows the shortest way, so montras fits.

Is mapo the subject or the object of montras?

Mapo is the subject, and la plej mallongan vojon is the direct object.

Structure of the subordinate clause:

• la mapo – subject (the map)
• montras – verb (shows)
• la plej mallongan vojon – direct object (the shortest way)

So literally: “the map shows the shortest way”.

Why do we say la plej mallongan vojon instead of la plej mallonga vojo here?

Both forms are grammatically possible, but they have different grammatical roles:

• la plej mallonga vojo – subject or complement (no -n)

  • La plej mallonga vojo estas tra la parko.
    The shortest way is through the park.

• la plej mallongan vojon – direct object (with -n)

  • La mapo montras la plej mallongan vojon.
    The map shows the shortest way.

In your sentence, “the shortest way” is what is being shown by the map, so it must be in the accusative: la plej mallongan vojon.

Why do both mallongan and vojon have the -n ending?

In Esperanto, adjectives agree with the noun they describe in:

• number (-j for plural)
• case (-n for accusative)

Here:

• Noun: vojo → vojon (accusative singular)
• Adjective: mallonga → mallongan (accusative singular to match vojon)

So we say:

• la mallongan vojon
• la longajn vojojn
• interesajn librojn, etc.

Marking -n on both is the standard, recommended form.

Does mallonga already mean “shortest”? Why do we need plej?

No. Mallonga by itself means simply “short”.

To form:

• Comparative “shorter”: pli mallonga
• Superlative “shortest”: plej mallonga

So:

• mallonga vojo – a short way
• pli mallonga vojo – a shorter way
• plej mallonga vojo – the shortest way

In your sentence you need “the shortest way”, so plej mallongan vojon is required.

Why is there la before plej in la plej mallongan vojon?

With superlatives, la usually appears to mean “the most / the -est”:

• plej longa – most long / longest (in general)
• la plej longa – the longest (a specific one)

So:

• plej mallonga vojo – a shortest way (rare context, more generic)
• la plej mallonga vojo – the shortest way (the specific one that is shortest)

Because we are clearly talking about the specific shortest route to the library, la plej mallongan vojon is natural.

Why doesn’t la biblioteko have the -n ending?

Because la biblioteko is governed by the preposition al (“to, towards”) and is not a direct object:

• la plej mallongan vojon – direct object of montras → gets -n
• al la biblioteko – prepositional phrase → no -n needed

In standard Esperanto, a noun after a preposition does not take -n, unless you are using a special optional accusative for direction without a preposition (e.g. mi iras hejmen = I go home).

Here, al already expresses direction, so we just say al la biblioteko.

Could I change the word order inside la plej mallongan vojon?

You have some freedom, but certain orders are more natural.

Standard order:

• la plej mallongan vojon – [article] [degree word] [adjective] [noun]

Possible but less common variants:

• la plej vojon mallongan – grammatically possible (thanks to -n), but sounds unusual and marked, used mainly for emphasis or poetic style.

For normal prose you should keep:

• la plej mallongan vojon

Can I drop la before biblioteko, and just say al biblioteko?

You can, but the meaning changes slightly.

• al la biblioteko – to the library (a specific, known library in context)
• al biblioteko – to a library (any library, not specified)

In many real situations you mean the local or known library, so al la biblioteko is the more natural choice here.