Pass auf, sonst verbrennst du dich am heißen Herd.

Because this is the informal singular imperative of aufpassen for du.

For most verbs, the du imperative is made from the du form of the present tense, but without -st:

• du passt auf → Pass auf!

In everyday German, the -e is often dropped in imperatives, so Passe auf! is grammatically possible but sounds more formal or old-fashioned. Pass auf! is the normal spoken form.

Because aufpassen is a separable verb.

The full verb is aufpassen, but in certain forms, the prefix moves to the end:

• du passt auf
• Pass auf!

This is very common in German:

• ankommen → Ich komme an
• mitbringen → Bring das mit

So Pass auf is just the imperative form of aufpassen.

Here aufpassen means to watch out, to be careful, or to pay attention.

It does not literally mean look up or anything involving physical upward movement. The meaning of separable verbs often cannot be guessed just from the parts.

In this sentence, Pass auf is a warning:

• Be careful
• Watch out

Sonst means otherwise.

It introduces the consequence of not doing what was just said:

• Pass auf, sonst verbrennst du dich.
• Be careful, otherwise you’ll burn yourself.

It is very common in warnings:

• Beeil dich, sonst verpasst du den Zug.
• Mach das Fenster zu, sonst wird es kalt.

Because sonst takes up the first position in the clause, and in a normal German main clause, the finite verb must be in second position.

So the structure is:

• Position 1: sonst
• Position 2: verbrennst
• then: du
• then the rest: dich am heißen Herd

This is standard German word order:

• Morgen gehe ich nach Berlin.
• Dann ruft er mich an.
• Sonst verbrennst du dich.

Because the verb here is used reflexively: sich verbrennen = to burn oneself.

Compare:

• etwas verbrennen = to burn something
• verbrennen = to burn / to be burned up
• sich verbrennen = to burn oneself

So:

• Du verbrennst das Essen. = You burn the food.
• Du verbrennst dich. = You burn yourself.

In this sentence, the person is the one who gets hurt, so German uses the reflexive pronoun dich.

Because sich verbrennen takes an accusative reflexive pronoun.

For du, the accusative reflexive pronoun is dich.

Reflexive pronouns can be accusative or dative depending on the verb:

• Du wäschst dich. = accusative
• Du putzt dir die Zähne. = dative

Here the whole idea is you burn yourself, so dich is correct:

• du verbrennst dich

Am is a contraction of an dem:

• an dem → am

So am heißen Herd literally means something like at/on the hot stove.

German often uses an with things you come into contact with or touch, especially surfaces or objects that cause the injury:

• sich am Messer schneiden = to cut oneself on the knife
• sich am Feuer wärmen = to warm oneself by the fire
• sich am Herd verbrennen = to burn oneself on the stove

So am heißen Herd is the place/object involved in the burning.

Because the adjective is following am, which is an dem, and dem is dative masculine singular here.

The noun Herd is masculine:

• der Herd

After dem, an adjective gets the ending -en:

• an dem heißen Herd
• contracted: am heißen Herd

So:

• der heiße Herd = nominative
• den heißen Herd = accusative
• dem heißen Herd = dative

Because German very often uses the present tense to talk about the future, especially when the future is clear from the context.

Here sonst makes it obvious that this is a future consequence:

• Pass auf, sonst verbrennst du dich.

English often uses you’ll burn yourself, but German naturally says du verbrennst dich.

German could also use wirst dich verbrennen, but that is less natural here and sounds heavier.

Not exactly. Der Herd usually means stove or cooker/range, depending on the variety of English.

It refers to the kitchen appliance used for cooking. In many contexts it especially suggests the stovetop, which makes sense here because that is something you can touch and burn yourself on.

If you specifically mean oven, German often uses:

• der Ofen = oven, stove, furnace, depending on context
• der Backofen = baking oven

So in this sentence, Herd is best understood as stove or cooker.

Yes, absolutely. That is a very common German pattern.

German often uses:

• reflexive pronoun in dative
  • body part in accusative

So:

• Du verbrennst dir die Hand. = You burn your hand.
• Du verbrennst dich. = You burn yourself.

Both are correct, but they focus slightly differently:

• du verbrennst dich = general
• du verbrennst dir die Hand = specifically your hand

With the rest of the sentence:

• Pass auf, sonst verbrennst du dir die Hand am heißen Herd.

It is informal, because it uses du and the du imperative:

• Pass auf

You would say this to a friend, child, family member, or someone you address as du.

In a formal situation with Sie, it would be:

• Passen Sie auf, sonst verbrennen Sie sich am heißen Herd.

So the original sentence is natural, everyday informal German.