La hejtado kaj la varma akvo ĉesis samtempe.

Because Esperanto verbs do not change for singular vs. plural subjects.

• mi ĉesis = I stopped
• li ĉesis = he stopped
• ili ĉesis = they stopped

So ĉesis works the same whether the subject is one thing or several things.

Because these words are the subject of the sentence, not the direct object.

The verb ĉesi means to stop / to cease, and it is normally intransitive here. That means it does not take a direct object in this sentence.

So:

• La hejtado ... ĉesis = the heating stopped
• la varma akvo ... ĉesis = the hot water stopped

No accusative -n is needed.

The suffix -ad- often gives the idea of an action that is ongoing, repeated, or viewed as a process.

• hejti = to heat
• hejtado = heating, the process/system of heating

In everyday usage, la hejtado can mean the heating in the practical sense, like the heating service or heating system in a building.

Repeating la is normal and often clearer when you join two noun phrases with kaj.

Here, the sentence is talking about two specific things:

• la hejtado = the heating
• la varma akvo = the hot water

Using la before both parts makes that very clear.

Sometimes Esperanto can omit a repeated article if the meaning is obvious, but in a sentence like this, repeating la sounds natural and avoids ambiguity.

Because akvo is usually treated as an uncountable noun, just like water in English.

So:

• varma akvo = hot/warm water

Also, the adjective varma agrees with akvo, which is singular, so it stays singular too.

It is not varmaj because it is not describing multiple separate waters.

In Esperanto, varma covers a range that can include both warm and hot, depending on context.

So varma akvo is the normal way to say hot water in many everyday situations.

If you want to emphasize that something is very hot, Esperanto can use:

• tre varma = very hot
• varmega = extremely hot

Ĉesis is the past tense form of ĉesi.

Esperanto tense endings are very regular:

• -as = present
• -is = past
• -os = future

So:

• ĉesas = stops / is stopping
• ĉesis = stopped
• ĉesos = will stop

Samtempe is an adverb, because it describes how the stopping happened: it happened at the same time.

The ending -e marks adverbs in Esperanto.

You can think of it roughly as built from the idea of same time:

• sama = same
• tempo = time
• samtempe = simultaneously / at the same time

Yes. Esperanto word order is fairly flexible, because the grammar is shown mostly by endings rather than strict position.

This sentence could also be written in other natural ways, such as:

• La hejtado kaj la varma akvo samtempe ĉesis.
• Samtempe ĉesis la hejtado kaj la varma akvo.

The original version is straightforward and neutral.

Because it modifies the verb ĉesis, not the nouns.

The sentence is saying that the heating and the hot water ceased simultaneously. That calls for an adverb, so Esperanto uses samtemp-e.

An adjective form like samtempa would need to describe a noun, not the action itself.

Ĉ is pronounced like ch in church.

So ĉesis sounds roughly like CHEH-sis.

A few pronunciation notes from this sentence:

• ĉ = ch
• j in kaj sounds like English y
• ŝ would sound like sh if it appeared, but it does not in this sentence

So kaj is pronounced roughly like kai / kahy, not like English cage or kay-j.