В душевой было жарко, поэтому я быстро принял душ и вышел.

Душевая means shower room or the shower area. It comes from the adjective душевой but is very commonly used as a noun.

In в душевой:

• в = in
• душевой is in the prepositional case because it shows location

So:

• душевая = the shower room
• в душевой = in the shower room

A learner might expect в душе, which can also mean in the shower, but в душевой focuses more on the room/area rather than the act or fixture itself.

Russian usually describes general conditions like it was hot, it was cold, it was dark with an impersonal construction:

• было жарко = it was hot
• было холодно = it was cold
• было темно = it was dark

Here:

• было is neuter singular past tense, used impersonally
• жарко is an adverb/predicative word, not an adjective agreeing with a noun

So было жарко does not mean something was hot in the adjective sense. It means the environment was hot.

Была жаркая would sound incomplete, because жаркая is an adjective and would need a noun, for example:

• была жаркая погода = the weather was hot

Поэтому means therefore, so, or that’s why. It introduces a result.

In this sentence:

• В душевой было жарко, поэтому я быстро принял душ и вышел.
• Literally: It was hot in the shower room, therefore I quickly took a shower and left.

Compare:

• потому что = because
• поэтому = therefore / so

So these are different in direction:

• Я быстро принял душ и вышел, потому что в душевой было жарко.
  = I quickly took a shower and left because it was hot in the shower room.

• В душевой было жарко, поэтому я быстро принял душ и вышел.
  = It was hot in the shower room, so I quickly took a shower and left.

Yes, принять often means to accept, to receive, or to take, but in Russian it is also part of several fixed expressions.

Принять душ is a standard expression meaning:

• to take a shower

It works like other common Russian collocations:

• принять ванну = to take a bath
• принять решение = to make a decision
• принять участие = to take part

So even though the literal core meaning of принять is broad, принять душ is just the normal idiomatic way to say take a shower.

This is about aspect.

• принял = perfective
• принимал = imperfective

Here the speaker is talking about a single completed action:

• he took a shower
• he finished it
• then he left

That is why the perfective принял is used.

Compare:

• Я принял душ и вышел.
  = I took a shower and left.
  Completed sequence.

• Я принимал душ, когда...
  = I was taking a shower when...
  Ongoing process.

So принял is natural because the action is viewed as a whole, completed event.

For the same reason: aspect.

• вышел = perfective, completed action
• выходил = imperfective, process/habit/repeated action

In this sentence the speaker means:

• he took a shower
• then he left

That is a clear chain of completed actions, so вышел is the natural choice.

Compare:

• Я вышел. = I went out / left.
• Я выходил. = I went out / had stepped out / used to go out, depending on context

Выходил would usually need a context that focuses on process, repetition, or background.

In Russian, past tense verbs agree with the gender of the subject.

With я, the form depends on whether the speaker is male or female:

• male speaker: я принял душ и вышел
• female speaker: я приняла душ и вышла

So this sentence suggests that the speaker is male.

If the speaker were female, the sentence would be:

• В душевой было жарко, поэтому я быстро приняла душ и вышла.

Because Russian often leaves out information that is obvious from context.

Here, the sentence already mentions в душевой, so after вышел it is easy to understand that the person left the shower room.

A fuller version would be:

• В душевой было жарко, поэтому я быстро принял душ и вышел из душевой.

But that sounds repetitive. Native speakers often omit the second mention when it is clear.

So:

• вышел = left / went out
• вышел из душевой = left the shower room

Both are possible; the shorter version is more natural here.

No, Russian word order is fairly flexible, although some orders sound more natural than others.

In this sentence:

• я быстро принял душ means I quickly took a shower

You could also say:

• я принял душ быстро

but that usually sounds a little more marked or contrastive, as if you are emphasizing quickly.

Possible variants:

• В душевой было жарко, поэтому я быстро принял душ и вышел.
• В душевой было жарко, поэтому я принял душ и быстро вышел.
• Я быстро принял душ и вышел, потому что в душевой было жарко.

These are all understandable, but they put emphasis in slightly different places.

The original version is natural because быстро modifies the shower-taking action in a straightforward way.

Yes, in many contexts it could.

For example:

• В душевой было жарко, поэтому я быстро помылся и вышел.

This would mean something like:

• It was hot in the shower room, so I washed up quickly and left.

The difference is:

• принять душ specifically means take a shower
• помыться means wash oneself, which is a little broader

So принял душ is more precise if you want to emphasize the shower itself.

Not exactly.

• душ can mean a shower or the shower fixture / showering
• душевая usually means the shower room or shower area

So:

• Я в душе = I’m in the shower
• Я в душевой = I’m in the shower room / shower area

In many everyday situations the difference may not matter much, but душевая is more about the place, while душ is more general.

Because поэтому connects two clauses, and Russian punctuation normally separates them with a comma.

Here the two parts are:

• В душевой было жарко
• поэтому я быстро принял душ и вышел

So the comma marks the boundary between:

• the cause/background
• the result

This is similar to English punctuation in a sentence like:

• It was hot in the shower room, so I quickly took a shower and left.

In Russian, the comma here is standard.