Fiul așteaptă în mașină.

Because -ul is the definite article in Romanian. Instead of using a separate word like English the, Romanian usually adds the article to the end of the noun.

• fiu = son
• fiul = the son

So Fiul așteaptă în mașină means The son is waiting in the car.

That is a normal feature of Romanian grammar. Romanian has a postposed definite article, which means the article comes at the end of the noun.

For example:

• băiat = boy
• băiatul = the boy
• mașină = car
• mașina = the car

So this sentence follows a very common Romanian pattern.

Așteaptă is the 3rd person singular present tense of the verb a aștepta, meaning to wait.

So it can mean:

• he waits
• she waits
• it waits

In this sentence, because the subject is fiul (the son), it means he is waiting or the son waits.

Romanian often uses the simple present tense where English may prefer the present continuous.

So:

• Fiul așteaptă can mean The son waits
• but in natural English, it is often translated as The son is waiting

This is very normal. Romanian does not need a separate verb like is in this sentence.

În means in, and mașină means car.

So în mașină means in the car or inside the car.

Here, în shows location.

Romanian sometimes leaves a noun indefinite after a preposition, especially when the meaning is clear from context. So în mașină can naturally be translated as in the car in English, even though word-for-word it looks like in car.

Both forms are possible, but they can feel slightly different depending on context:

• în mașină = in a car / in the car
• în mașina = in the car with a more clearly definite sense

In many everyday sentences, Romanian does not always mark definiteness the same way English does.

Mașină is the basic dictionary form of the noun and it is a feminine singular noun.

That final -ă is a very common ending in Romanian feminine nouns:

• casă = house
• masă = table
• mașină = car

So nothing unusual is happening here; it is just the normal singular form.

A rough pronunciation guide is:

• așteaptă ≈ uh-SHTEAP-tuh
• mașină ≈ muh-SHEE-nuh

A few useful sound notes:

• ș sounds like sh in shoe
• ă is a short neutral vowel, like the a in about
• ț would sound like ts, but it does not appear in this sentence

So:

• așteaptă has the sh sound because of ș
• both așteaptă and mașină end with ă, that neutral Romanian vowel

Yes. Romanian often drops the subject pronoun when the verb form already shows the person.

So instead of saying:

• El așteaptă în mașină = He is waiting in the car

Romanian can simply say:

• Așteaptă în mașină = He/She is waiting in the car

In your sentence, fiul is included because the speaker wants to specify the son as the subject.

The basic order here is very natural:

• Fiul așteaptă în mașină.

Romanian word order is somewhat flexible, but different orders can change emphasis.

For example:

• În mașină așteaptă fiul. = puts more emphasis on in the car
• Așteaptă în mașină fiul. = possible, but less neutral

For a learner, Subject + Verb + prepositional phrase is the safest and most natural pattern here.

No. In this sentence, în mașină means in the car, meaning location.

If you want to say by car, Romanian usually says:

• cu mașina = by car / with the car

So compare:

• Fiul așteaptă în mașină. = The son is waiting in the car.
• Fiul merge cu mașina. = The son goes by car.

After în with a location meaning, Romanian uses the accusative form. In practice, for many nouns, that looks the same as the basic form.

So in:

• în mașină

mașină is in the form normally used after the preposition în.

For a beginner, the important thing is:

• în
  • noun = often means in/inside
• learn common preposition patterns as whole chunks, such as în casă, în oraș, în mașină

Both are possible, but they are not exactly the same.

• fiul = the son
• băiatul = the boy

Fiul specifically shows a family relationship, so it means someone’s son. It is correct, but in everyday conversation the choice depends on context. If the speaker is talking about a family member, fiul is perfectly natural.

So this sentence is grammatically normal; it just gives a slightly more specific meaning than the boy is waiting in the car.