Medicul cheamă asistenta.

Because Romanian usually puts the definite article at the end of the noun, not in front of it.

• medic = doctor
• medicul = the doctor

So -ul here means the for a masculine singular noun.

This is very different from English, where the is a separate word.

Asistentă is the basic form, meaning a nurse or a female assistant.

When Romanian makes it definite, the nurse, the ending changes:

• asistentă = a nurse
• asistenta = the nurse

So the final ă changes to a in the definite form. This is a normal pattern for many feminine nouns ending in -ă.

Cheamă is the 3rd person singular present form of a chema = to call.

So:

• eu chem = I call
• tu chemi = you call
• el/ea cheamă = he/she calls

In this sentence, cheamă matches medicul, which is singular: the doctor calls.

Not necessarily.

A chema often means to call someone over, summon, send for, ask to come, not just phone someone.

So in Medicul cheamă asistenta, the natural sense is usually something like The doctor calls for the nurse or The doctor calls the nurse over, depending on context.

Romanian often leaves subject pronouns out when they are not needed.

The verb ending already shows the person and number:

• cheamă = he/she calls

So instead of saying something like El cheamă asistenta, Romanian very often just says Medicul cheamă asistenta.

This is normal and very common.

In a simple neutral sentence like this, Romanian usually follows subject + verb + object, just like English:

• Medicul = subject
• cheamă = verb
• asistenta = object

So the default reading is The doctor calls the nurse.

That said, Romanian word order can be more flexible than English, especially when speakers want to add emphasis. Context also helps.

In very natural standard Romanian, many speakers would prefer:

• Medicul o cheamă pe asistentă.

This is because a specific human direct object is often marked with pe, and very often also doubled with a short pronoun like o.

So:

• pe asistentă marks the nurse as the direct object
• o repeats that object in clitic form

The sentence you were given, Medicul cheamă asistenta, is still understandable and is common in simplified learning material, especially when the goal is to show basic structure. But in everyday Romanian, Medicul o cheamă pe asistentă is often the more idiomatic version if you mean a particular nurse.

A rough English-friendly guide is:

• Medicul ≈ meh-DEE-cool
• cheamă ≈ KYAH-muh or KEAH-muh
• asistenta ≈ ah-sees-TEN-ta

A few useful pronunciation notes:

• ch before e gives a k sound, so cheamă does not start like English chair
• ă is a short central vowel, something like a relaxed uh
• stress is usually:
  • meDIcul
  • CHEAmă
  • asisTENta

Yes, Romanian can change word order more easily than English, usually for emphasis or contrast.

The neutral order is:

• Medicul cheamă asistenta.

A more marked version might be:

• Pe asistentă o cheamă medicul.

That still means It’s the doctor who is calling the nurse, but with a different emphasis.

So for learners, the safest first pattern is the basic one: subject + verb + object.