Спасательница показала детям, как помочь пострадавшему до приезда врача.

Спасательница is the feminine form of спасатель and means a female rescuer / female lifeguard / female emergency worker, depending on context.

Russian often has:

• спасатель = masculine form
• спасательница = explicitly feminine form

In modern Russian, the masculine job title can sometimes be used generically, but спасательница makes it clear that the rescuer is a woman.

This also affects the verb:

• спасательница показала = the female rescuer showed
• спасатель показал = the male rescuer showed

So the noun and past-tense verb match in gender.

In the past tense, Russian verbs agree with the subject in gender and number.

For показать in the past tense:

• показал = masculine singular
• показала = feminine singular
• показало = neuter singular
• показали = plural

Since the subject is спасательница, which is feminine singular, the correct form is показала.

Because показать uses the pattern:

• показать кому? что?
• to show someone something

The person who receives what is shown goes in the dative case. So:

• дети = children
• детям = to the children

Here, детям is the indirect object: the rescuer showed the children how to help.

The direct object is not a single noun here. Instead, it is the whole clause:

как помочь пострадавшему до приезда врача

After показать, Russian can use a clause meaning how to do something. So the structure is:

• Спасательница показала детям ... = The rescuer showed the children ...
• как помочь пострадавшему... = how to help the injured person ...

So the whole как-clause functions as the thing that was shown.

Because как помочь пострадавшему до приезда врача is a subordinate clause.

Russian normally puts a comma before subordinate clauses introduced by words like что, как, когда, если, and so on.

So the sentence is divided like this:

• main clause: Спасательница показала детям
• subordinate clause: как помочь пострадавшему до приезда врача

That is why the comma is required.

After verbs like показать, объяснить, научить, Russian often uses:

• как + infinitive

This is a very common way to say how to do something.

Examples:

• показать, как плавать = to show how to swim
• объяснить, как пользоваться = to explain how to use
• научить, как готовить = to teach how to cook

So как помочь literally means how to help.

A finite verb would change the meaning or make the structure less natural here.

This is an aspect question.

• помочь = perfective
• помогать = imperfective

Here, помочь is used because the sentence is about performing a concrete helpful action in a specific situation: giving help to an injured person before the doctor arrives.

So как помочь пострадавшему means something like:

• how to help the injured person
• how to give effective aid in that situation

If you used как помогать, it would sound more like:

• how to help in general
• how to be helping
• the general process or manner of helping

So помочь is the natural choice for a specific emergency action.

Because помочь takes the dative:

• помочь кому?
• to help whom?

So:

• пострадавший = injured person / victim
• пострадавшему = to the injured person / victim

This is different from English, where help takes a direct object. In Russian, помочь works more like give help to someone, so the person being helped is in the dative.

Пострадавший originally comes from a participle related to пострадать = to suffer / to be injured / to be harmed. In practice, though, it is very often used as a noun meaning:

• injured person
• victim
• casualty

It declines like an adjective, which is why the forms look adjectival:

• пострадавший = nominative masculine singular
• пострадавшего = accusative/genitive masculine singular
• пострадавшему = dative masculine singular

This kind of word is sometimes called a substantivized adjective/participle: it looks like an adjective, but functions like a noun.

Because of two separate grammar points.

1. до requires the genitive case. So:

   • до приезда = before / until the arrival

2. врача depends on приезда. The phrase means the doctor's arrival or arrival of the doctor, so врача is also genitive.

Breakdown:

• приезд = arrival
• приезда = of the arrival / arrival (after до)
• врач = doctor
• врача = of the doctor

So:

• до приезда врача = before the doctor's arrival / until the doctor arrives

Both are possible, but they are slightly different in style.

• до приезда врача is more compact and a bit more formal or written
• пока врач не приедет is a full clause and sounds a bit more conversational

Russian often likes noun phrases after prepositions, especially in informative or instructional language. In emergency or educational contexts, до приезда врача sounds very natural.

So this sentence has a slightly concise, instructional feel:

• how to help the injured person before the doctor's arrival

The word order is quite neutral and natural.

• Спасательница показала детям, как помочь пострадавшему до приезда врача.

This flows as:

1. subject: спасательница
2. verb: показала
3. recipient: детям
4. content: как помочь...

Russian word order is flexible, so other versions are possible, such as:

• Детям спасательница показала, как помочь пострадавшему...
• Как помочь пострадавшему до приезда врача, спасательница показала детям.

But those alternatives shift emphasis. The original sentence is the most straightforward, neutral version.