Ο ασθενής περιμένει ήρεμα τη γιατρό στο νοσοκομείο.

Ασθενής is originally an adjective, but it is very commonly used as a noun meaning patient.

In this sentence, ο ασθενής means the male patient.
If the patient were female, it would be η ασθενής.

So this is a good example of a Greek word whose article helps show gender:

• ο ασθενής = male patient
• η ασθενής = female patient

The word itself stays the same.

Περιμένει is the 3rd person singular present form of περιμένω = to wait.

So it means:

• he/she waits
• he/she is waiting

Greek present tense often covers both the simple present and the progressive idea that English separates.

Here, because of the context, English would usually translate it as is waiting.

Because ήρεμα is an adverb, and it describes how the patient is waiting.

• ήρεμος / ήρεμη / ήρεμο = calm, quiet
• ήρεμα = calmly

So:

• ο ασθενής είναι ήρεμος = the patient is calm
• ο ασθενής περιμένει ήρεμα = the patient waits calmly

In this sentence, the word modifies the verb περιμένει, not the noun ασθενής.

In Modern Greek, γιατρός can refer to either a male or a female doctor. The article tells you the gender:

• ο γιατρός = the male doctor
• η γιατρός = the female doctor

So τη γιατρό means the female doctor in the accusative case.

This is common with some profession nouns in Greek: the noun form may stay the same for both genders, while the article changes.

Because the doctor is the direct object of the verb περιμένει.

The patient is doing the action of waiting, and the doctor is the person being waited for. In Greek, direct objects normally go in the accusative.

So:

• nominative: η γιατρός = the female doctor
• accusative: τη(ν) γιατρό = the female doctor

You can see two changes:

• the article changes from η to τη(ν)
• the noun changes from γιατρός to γιατρό

The full accusative form of the feminine article is την, but in everyday Greek the final -ν is often dropped before certain consonants.

So both of these may be seen:

• την γιατρό
• τη γιατρό

In this sentence, τη γιατρό is perfectly natural.

A simple learner rule is:

• την is the full form
• τη is a very common shortened form before consonants

Στο is a contraction of:

• σε = in, at, to
• το = the

So:

• σε + το = στο

This kind of contraction is extremely common in Greek:

• στο = in/at/to the
• στη = in/at/to the
• στον = in/at/to the

So στο νοσοκομείο literally means in/at/to the hospital.

Because νοσοκομείο is a neuter noun, and in the singular its nominative and accusative forms are the same.

So:

• το νοσοκομείο = the hospital
• στο νοσοκομείο = in/at/to the hospital

The noun itself stays νοσοκομείο. What changes is the article/preposition combination.

This is very common with neuter nouns in Greek.

It can mean either, depending on context, because σε often covers meanings that English separates into in, at, and to.

Here, with περιμένει = is waiting, the natural meaning is at the hospital.

So in this sentence, στο νοσοκομείο is understood as a location, not a destination.

Not as fixed as in English.

Greek has more flexibility because articles and endings help show grammatical roles. This means you can move parts of the sentence around for emphasis.

The given order is very natural:

• Ο ασθενής περιμένει ήρεμα τη γιατρό στο νοσοκομείο.

But other orders are also possible, for example:

• Ο ασθενής περιμένει τη γιατρό ήρεμα στο νοσοκομείο.
• Στο νοσοκομείο ο ασθενής περιμένει ήρεμα τη γιατρό.

These versions can sound slightly different in focus, but the basic meaning stays the same.

Yes. In Greek, the accent mark shows which syllable is stressed, and correct stress is important.

In this sentence:

• ασθενής
• περιμένει
• ήρεμα
• γιατρό
• νοσοκομείο

If you put the stress on the wrong syllable, your Greek may sound unnatural or may even become confusing.

So it is worth learning each word together with its stress, not just its spelling.