Schalte die Herdplatte bitte aus, bevor du gehst.

Because this is a command in German, so it uses the imperative.

The normal statement would be something like:

• Du schaltest die Herdplatte aus. = You turn off the burner.

But when giving a command to du, German usually drops the subject du and uses the imperative form:

• Schalte ... aus! = Turn ... off!

So Schalte die Herdplatte bitte aus is the command form addressed to one person informally.

The verb is schalten. For the du-imperative, German usually removes -st from the normal du form:

• du schaltest → imperative schalte

Also, verbs whose stem ends in -t or -d often keep an extra -e in the imperative because it is easier to pronounce.

So:

• schalten → Schalte!
• compare: arbeiten → Arbeite!

You may sometimes hear shortened forms in casual speech, but Schalte is the standard form learners should use.

Because ausschalten is a separable verb.

The full verb is:

• ausschalten = to switch off / turn off

In many sentence types, German splits this verb into two parts:

• schalte ... aus

So:

• Schalte die Herdplatte bitte aus.

This is very common with separable verbs:

• Ich mache das Licht aus.
• Ruf mich bitte an.
• Steh früh auf.

The prefix often goes to the end of the clause.

Die Herdplatte means the burner / hotplate / stove plate on a stove.

It is a feminine noun:

• die Herdplatte

Depending on the kind of stove and the variety of English, it may be translated as:

• burner
• hotplate
• stovetop plate

So in this sentence it means the part of the stove that should be turned off before leaving.

Because Herdplatte is a feminine noun, so its basic article is:

• die Herdplatte

In this sentence, it is the direct object of schalten ... aus, and in the accusative feminine, die stays die.

So:

• nominative: die Herdplatte
• accusative: die Herdplatte

That is why you see die here.

Bitte is flexible in German, but some positions sound more natural than others.

In this sentence:

• Schalte die Herdplatte bitte aus

bitte softens the command: please

It often appears:

• after the object: Schalte die Herdplatte bitte aus
• or earlier: Bitte schalte die Herdplatte aus

Both are fine. The version in your sentence sounds very natural.

German does not always place bitte exactly where English places please, so it is best to learn common patterns rather than translating word-for-word.

Because bevor introduces a subordinate clause, and subordinate clauses in German are normally separated by a comma.

So the sentence has two parts:

• Schalte die Herdplatte bitte aus
• bevor du gehst

The comma marks the boundary between the main clause and the subordinate clause.

This is standard German punctuation.

The verb here is gehen.

Its du form in the present tense is:

• du gehst = you go / you are going

So:

• bevor du gehst = before you go / before you leave

There is nothing unusual here; gehst is just the normal du form of gehen.

Because bevor creates a subordinate clause, and in German subordinate clauses, the conjugated verb usually goes to the end.

Compare:

Main clause word order:

• Du gehst.

Subordinate clause word order:

• ..., bevor du gehst.

This happens with many subordinating conjunctions, such as:

• weil = because
• dass = that
• wenn = if/when
• bevor = before

Examples:

• Ich bleibe hier, weil ich müde bin.
• Sag mir, wenn du Zeit hast.

So gehst is at the end because of bevor.

In the first clause, the sentence is a command, so German normally leaves out du:

• Schalte ... aus

In the second clause, however, it is not a command. It is a normal subordinate clause with a subject and a verb:

• bevor du gehst

So the subject du has to be stated there.

In other words:

• first clause = imperative, subject usually omitted
• second clause = regular clause, subject included

Yes, absolutely.

German allows either order:

• Schalte die Herdplatte bitte aus, bevor du gehst.
• Bevor du gehst, schalte die Herdplatte bitte aus.

Both mean the same thing.

When the bevor clause comes first, it is followed by a comma, and then the main clause begins. Since the main clause here is an imperative, it still starts naturally with:

• schalte

So both versions are correct and idiomatic.

It is informal, because it uses the du form.

You can tell from:

• the imperative Schalte
• the subordinate clause bevor du gehst

If you wanted to say this to someone formally, using Sie, you would say:

• Schalten Sie bitte die Herdplatte aus, bevor Sie gehen.

So the original sentence is addressed to one person you would call du.

It can definitely be used for a stove burner too.

Ausschalten is used for many things that are turned off, including:

• lights
• devices
• appliances
• burners / hotplates

So die Herdplatte ausschalten is natural German.

You may also hear related verbs in other contexts, such as:

• ausmachen
• abstellen

But ausschalten is completely normal here.