L’échappement est sous la voiture.

Because échappement is a singular noun, and in this sentence it uses the definite article le (the).
Before a vowel sound, le contracts to l’ for easier pronunciation:

• le échappement → l’échappement

This is called elision.

It is masculine.

That is why the full article is le échappement, which becomes l’échappement.

You can tell it is masculine from things like:

• un échappement
• l’échappement est cassé (with a masculine adjective)

In this context, échappement means exhaust or exhaust system of a car.

French often uses échappement where English speakers might say:

• the exhaust
• the exhaust pipe
• the car’s exhaust system

The exact English wording depends on context, but in this sentence it refers to the car part underneath the vehicle.

Because the sentence is describing location, not possession.

• sous la voiture = under the car
• de la voiture = of the car / from the car

So:

• L’échappement est sous la voiture = the exhaust is physically under the car

If you said l’échappement de la voiture, that would mean the car’s exhaust or the exhaust of the car, which identifies which exhaust you mean, rather than where it is.

Sous is a preposition meaning under or beneath.

It is followed directly by a noun phrase:

• sous la voiture = under the car
• sous la table = under the table
• sous le lit = under the bed

Unlike in English, you do not need any extra word like the one that is. French just uses sous + noun.

Because voiture is a feminine noun.

So the definite article is la:

• la voiture = the car

Compare:

• le camion = the truck
• la voiture = the car

Since voiture begins with a consonant sound, the article stays la and does not contract.

Est is the third-person singular form of être (to be).

The subject is l’échappement, which is singular, so French uses:

• il est / l’échappement est = it is / the exhaust is

This is the normal way to state location:

• Le livre est sur la table.
• La clé est dans la voiture.
• L’échappement est sous la voiture.

Yes, very close.

French:

• L’échappement (subject)
• est (verb)
• sous la voiture (location)

English:

• The exhaust
• is
• under the car

So the structure is straightforward: subject + verb + prepositional phrase

A simple approximate pronunciation is:

lay-shaap-mon ay soo la vwah-tyur

A few notes:

• é sounds like ay
• ch in échappement sounds like sh
• the ending -ment is nasal, so it is not pronounced like English ment
• est is usually pronounced ay here
• sous sounds like soo
• voiture sounds roughly like vwah-tyur

If you want to sound more natural, try saying it smoothly as one rhythm group: L’échappement est sous la voiture.

No, that would be ungrammatical in standard French.

French usually needs articles where English sometimes drops them. In this sentence, both nouns normally take definite articles:

• l’échappement
• la voiture

So the correct sentence is: L’échappement est sous la voiture.

Yes, but it is a little different in style.

• sous la voiture = under the car
• en dessous de la voiture = underneath / below the car

Both are correct, but sous is shorter and more basic. In a simple sentence like this, sous la voiture is the most natural choice.

Because French uses elision before a vowel sound.

• le + échappement → l’échappement
• la + voiture stays la voiture, because voiture starts with a consonant sound

So the apostrophe appears only when the article loses a vowel before the next word.

It is normally literal.

It simply describes where the exhaust is located: under the car.

There is no special idiomatic meaning here. It is a straightforward sentence about a physical object and its position.