Learn Hardcore Esperanto: Kiam li ne komprenas, li petas ŝin helpi, kaj ŝi proponas alian solvon. - When he does not understand, he asks her to help, and she proposes another solution.

Kiam means “when” (at the time that), while se means “if” (on the condition that).
The sentence describes what happens whenever he doesn’t understand, not a hypothetical condition.

Kiam li ne komprenas… = Whenever/when he doesn’t understand…
Se li ne komprenas… would mean If he doesn’t understand… (more conditional, speculative).

So kiam is chosen because this is a regular, repeated situation rather than a mere possibility.

Why is the verb komprenas in the present tense? Wouldn’t a past or future tense make more sense?

Esperanto, like English, uses the present tense for general, repeated, or habitual actions.

Kiam li ne komprenas, li petas ŝin helpi… corresponds to English “When he doesn’t understand, he asks her to help…” — also present simple.

It does not mean “right now” specifically; it means “whenever that situation arises”, which is why the simple present is correct.

Why is there a comma after komprenas?

In Esperanto, it’s standard to put a comma between a subordinate clause and the main clause:

Kiam li ne komprenas, li petas ŝin helpi…
- Kiam li ne komprenas = subordinate clause (time clause)
- li petas ŝin helpi = main clause

That comma is similar to English in “When he doesn’t understand, he asks her to help…”.
The comma before kaj is optional here, but many writers keep it to separate the second main clause: …, kaj ŝi proponas…

What is the role of ŝin in li petas ŝin helpi? Why does it have -n?

Ŝi = “she” (subject form).
Ŝin = “her” (object form, using the accusative -n).

In li petas ŝin helpi:

li = subject (“he”)
petas = verb (“asks, requests”)
ŝin = direct object (“her”) — the person he is asking
helpi = infinitive (“to help”) — what he is asking her to do

The -n on ŝin marks her as the direct object of petas.

Why is it li petas ŝin helpi and not something like li petas por helpo?

In Esperanto, peti usually takes a direct object:

Peti iun fari ion = “to ask someone to do something”
- Mi petas vin veni. = “I ask you to come.”
- Li petas ŝin helpi. = “He asks her to help.”
Peti ion (de iu) = “to ask for something (from someone)”
- Mi petas helpon de vi. = “I ask for help from you.”

So li petas ŝin helpi follows pattern (1):
he asks her (ŝin) to help (helpi).
Pori/pra “por helpo” would sound more like “for help” as a noun, not “to help” as an action.

Who is doing the helping in li petas ŝin helpi? Is it clear that she is the one who helps?

Yes. In Esperanto, when you have peti iun fari ion, the person after peti is normally understood as the subject of the infinitive:

Li petas ŝin helpi. = He asks her to help.
Mi petas vin veni. = I ask you to come.

So ŝin is understood as the one who will helpi.
If you wanted to emphasize whom she helps, you could say:

Li petas ŝin helpi lin. = He asks her to help him.

Could we also say li petas, ke ŝi helpu instead of li petas ŝin helpi? What’s the difference?

Yes, that’s a very natural alternative:

Li petas ŝin helpi.
Li petas, ke ŝi helpu.

Both mean essentially “He asks her to help.”

Differences:

ŝin helpi uses an infinitive; it’s a bit more compact and slightly more colloquial in style.
ke ŝi helpu uses a “ke”-clause with a verb in a finite form (here, helpu, the volitive/subjunctive-like mood). It can feel more explicit: he asks that she help.

Both are good Esperanto; style and context decide which you prefer.

Why is it ŝi proponas alian solvon and not ŝi proponas alian solvo?

In Esperanto, direct objects take the accusative -n ending.
Solvo = “solution” (nominative),
solvon = “solution” as direct object.

Since ŝi proponas alian solvon — she proposes another solution — solvon is the direct object of proponas, so it needs -n.

Because alia is an adjective describing solvon, it must agree in case and number:

alia solvo (subject, singular)
alian solvon (direct object, singular)

So both alia and solvo receive -n: alian solvon.

Why is there no article la in ŝi proponas alian solvon?

La is the definite article (“the”). Here, she is proposing “another solution”, not a particular known solution.

ŝi proponas alian solvon = “she proposes another solution” (unspecified, indefinite).
ŝi proponas la alian solvon = “she proposes the other solution” (a specific one already known in the context).

Because the sentence talks about any different solution, not a specific, previously mentioned one, there is no la.

What exactly does alia add in alian solvon? Could we just say ŝi proponas solvon?

Yes, you could say ŝi proponas solvon, which means simply “she proposes a solution.”

Adding alia (“other, another”) makes it clear that this solution is different from some previous or current one:

ŝi proponas solvon = she proposes a solution.
ŝi proponas alian solvon = she proposes another/different solution (as an alternative to the existing one).

So alia emphasizes the contrast with a solution that has already been considered.

Why is the pronoun ŝi used twice (ŝin, ŝi) instead of repeating her name or using some shorter form?

Esperanto regularly reuses personal pronouns just like English uses “she / her”.

li petas ŝin helpi, kaj ŝi proponas alian solvon.

Here:

ŝin = “her” (object) in the first clause,
ŝi = “she” (subject) in the second clause.

Repeating ŝi makes it grammatically clear that she (the same woman) is now the subject of the new action proponas. Esperanto doesn’t have special clitic forms like “’er” or “’im”; you just use the full pronouns.

Is proponi used like English “propose” or “suggest”? Does it need any preposition?

Proponi is a straightforward transitive verb: to propose / to offer / to suggest something.

Ŝi proponas alian solvon. = She suggests another solution.

No extra preposition is required with the thing being proposed; it’s a direct object:

proponi ideon = to propose/suggest an idea
proponi planon = to propose a plan

If you want to mention the person to whom you propose it, you usually add al:

Ŝi proponas alian solvon al li. = She proposes another solution to him.

Could we change the word order in li petas ŝin helpi or ŝi proponas alian solvon?

Yes, Esperanto word order is fairly flexible, because endings show the grammatical roles. For example:

Li petas ŝin helpi.
Li petas helpi ŝin. (≠ same meaning)
Ŝi proponas alian solvon.
Alian solvon ŝi proponas.

Be careful with li petas helpi ŝin: that usually means “he asks to help her” (he wants to be the one helping), because ŝin is now clearly object of helpi.

The original li petas ŝin helpi means “he asks her to help (someone/somehow)”, where ŝi (ŝin) is understood as the subject of helpi. The endings -n and context tell you who does what.