Compania aeriană localizează valiza.

Because compania means the company, while companie means a company or just company in a dictionary form.

Romanian usually adds the definite article to the end of the noun instead of putting a separate word like the in front.

• companie = company
• compania = the company

So compania aeriană means the airline or literally the air company.

For the same reason: valiza is the definite form, meaning the suitcase.

• valiză = suitcase
• valiza = the suitcase

Romanian often marks the by changing the end of the noun.

In Romanian, adjectives often come after the noun, unlike English, where they usually come before it.

So:

• companie aeriană = air company / airline
• literally: company air-related

This is the normal order in Romanian. You will often see:

• mașină roșie = red car
• casă mare = big house

Because the adjective has to agree with the noun in gender and number.

Companie is a feminine singular noun, so the adjective must also be feminine singular:

• masculine singular: aerian
• feminine singular: aeriană

So:

• zbor aerian would sound odd because zbor already means a flight, but grammatically it would use the masculine form
• companie aeriană uses the feminine form because companie is feminine

Localizează is the 3rd person singular present tense of the verb a localiza.

So it matches compania aeriană = the airline, which is a third-person singular subject:

• eu localizez = I locate
• tu localizezi = you locate
• el/ea localizează = he/she/it locates
• compania localizează = the company locates

In this sentence, it can mean both:

• locates
• is locating

Romanian present tense often covers both the simple present and the present progressive from English.

It can mean either one, depending on context.

Romanian does not usually make the same strong distinction English does between:

• locates
• is locating

So Compania aeriană localizează valiza could mean:

• The airline locates the suitcase
• The airline is locating the suitcase

Context tells you which is more natural.

Often, yes. Romanian is a language that can drop the subject when it is clear from the verb ending or context.

For example:

• Localizează valiza. = It/He/She is locating the suitcase or Locates the suitcase, depending on context

But in your sentence, Compania aeriană is included to make it clear who is doing the action.

The normal, neutral order is Subject + Verb + Object:

• Compania aeriană localizează valiza.

That is the most straightforward order.

Romanian word order is more flexible than English, though, so other orders are possible for emphasis. For example, you might move valiza earlier if you want to highlight it. But for a basic statement, the given order is the most natural.

The Romanian ă is a short, neutral vowel sound, similar to the a in English sofa for many speakers.

So:

• aeriană ends with -nă
• localizează ends with -ză

It is not pronounced like a full a in father.

A rough pronunciation guide for the whole sentence is:

kom-PA-nee-a ae-rea-NƏ lo-ka-li-ZEA-zə va-LI-za

That is only approximate, but it helps show where the stress roughly falls.

Here are the base forms:

• compania → companie = company
• aeriană → aerian / aeriană = aerial, air-related
• localizează → a localiza = to locate
• valiza → valiză = suitcase

This is useful because Romanian often changes word endings for definiteness, agreement, and verb conjugation.

You would use the indefinite noun forms:

• O companie aeriană localizează o valiză.

That means An airline is locating a suitcase or An airline locates a suitcase.

Compare:

• Compania aeriană localizează valiza. = The airline locates the suitcase
• O companie aeriană localizează o valiză. = An airline locates a suitcase

Romanian uses o for feminine singular indefinite nouns here.