Die Hitze schadet dem Reifen.

Because the verb schaden takes the dative case, not the accusative.

• schaden + dative = to be harmful to someone/something
• So:
  • dem Reifen = to the tire / the tire as the thing affected

For a native English speaker, this is important because English does not show this kind of case marking clearly, but German does.

Die Hitze is in the nominative case because it is the subject of the sentence — the thing doing the action, or in this case, causing the harm.

So the structure is:

• Die Hitze = subject, nominative
• schadet = verb
• dem Reifen = dative object

Hitze is a feminine noun, so its article in the nominative singular is die.

So:

• die Hitze = feminine singular nominative

This is not the plural here. The noun Hitze is singular, and the verb schadet is also singular, which confirms that.

Yes, in its normal use, schaden takes a dative object.

Examples:

• Das schadet mir. = That harms me.
• Rauchen schadet der Gesundheit. = Smoking harms health.
• Die Hitze schadet dem Reifen.

So when you use schaden, you should expect the person or thing being harmed to be in the dative.

Yes, but then the meaning changes slightly: den Reifen would be plural dative.

So:

• dem Reifen = the tire / one tire
• den Reifen = the tires / multiple tires

So Die Hitze schadet den Reifen would mean The heat harms the tires.

Because not every German verb takes an accusative object.

English learners often expect a pattern like:

• subject + verb + direct object

But German verbs have different case patterns.
With schaden, the affected thing is not accusative — it is dative.

So this sentence is complete as it is:

• Die Hitze = nominative subject
• schadet = verb
• dem Reifen = dative object

Yes. German word order is flexible, but the finite verb usually stays in the second position in a main clause.

Normal order:

• Die Hitze schadet dem Reifen.

You could also say:

• Dem Reifen schadet die Hitze.

This puts more emphasis on dem Reifen, but the meaning stays the same because the case endings show who is doing what:

• die Hitze = nominative subject
• dem Reifen = dative object

Reifen usually means tire — the rubber outer part.

Rad usually means wheel, and in some contexts it can also mean bicycle.

So in this sentence, Reifen is the correct word if you mean that heat is damaging the tire itself.

Yes. schadet is the third-person singular form of schaden, and it matches the singular subject die Hitze.

The verb forms are:

• ich schade
• du schadest
• er/sie/es schadet
• wir schaden
• ihr schadet
• sie/Sie schaden

Because die Hitze is singular, you use schadet.

Yes, grammatically that works too. Die Wärme also means heat/warmth, but it can sound a little different in tone or usage depending on context.

• Hitze often suggests strong heat
• Wärme can be more general or milder

So Die Hitze schadet dem Reifen strongly suggests damaging heat, which often fits the context better.