Ni komencos fizioterapion, krom se la kuracisto diros ne.

Komencos is the future tense of komenci and means will begin / will start.

So:

• Ni komencos = We will start
• Ni komencas = We are starting / We start

In this sentence, the speaker is talking about a future action, so komencos is the natural choice.

The -n ending marks the direct object in Esperanto.

Here, fizioterapion is the thing being started:

• Ni komencos fizioterapion = We will start physiotherapy

The action komenci takes an object, and that object gets -n.

Compare:

• Mi legas libron. = I am reading a book.
• Ni komencos fizioterapion. = We will start physiotherapy.

Without the -n, the grammar would be wrong in standard Esperanto.

Krom se means unless.

Literally, it is something like except if:

• krom = except, besides
• se = if

So:

• Ni komencos fizioterapion, krom se la kuracisto diros ne.
• We will start physiotherapy, unless the doctor says no.

This is a very common and useful expression in Esperanto.

La kuracisto means the doctor, referring to a specific doctor known from the situation.

In Esperanto, la is the definite article, like English the.

So:

• kuracisto = a doctor / doctor
• la kuracisto = the doctor

In this sentence, the speaker presumably means a particular doctor involved in the decision, so la makes sense.

This is a very common question for English speakers.

Esperanto often uses the tense more logically and directly than English does. Since the doctor’s refusal would happen in the future, Esperanto uses the future tense:

• la kuracisto diros ne = the doctor will say no

Even though English usually prefers present tense after unless or if, Esperanto commonly keeps the future meaning explicit.

So this is normal Esperanto, even if it feels slightly different from English.

Diri ne means to say no.

So:

• diros = will say
• ne = no / not

In this expression, ne functions like the word no in English.

Examples:

• Ŝi diris jes. = She said yes.
• Li diris ne. = He said no.

So la kuracisto diros ne means the doctor will say no or the doctor will refuse.

Yes, it could, but the meaning would be slightly different in tone.

• diros ne = will say no
• rifuzos = will refuse

Diros ne is very natural and straightforward, and it closely matches the idea of someone verbally saying no.
Rifuzos sounds a bit more formal or more specifically like a refusal.

So:

• Ni komencos fizioterapion, krom se la kuracisto diros ne.
• Ni komencos fizioterapion, krom se la kuracisto rifuzos.

Both are possible, but the original sentence is perfectly natural.

Not completely. Esperanto word order is fairly flexible, though some orders sound more natural than others.

The given sentence:

• Ni komencos fizioterapion, krom se la kuracisto diros ne.

is the most straightforward and natural order.

Because Esperanto marks grammar with endings, some parts can move around:

• Krom se la kuracisto diros ne, ni komencos fizioterapion.

This means the same thing, but it puts the condition first, like:

• Unless the doctor says no, we will start physiotherapy.

So the word order can change for emphasis, but the original version is very standard.

Because komenci can take a direct object directly.

In this sentence, the thing being started is physiotherapy, so Esperanto simply uses the noun:

• komenci fizioterapion = to start physiotherapy

If you wanted to say start doing physiotherapy, you could also express that more explicitly, but it is not necessary here.

Esperanto often prefers the simpler structure when the meaning is clear.

It can mean either, depending on context.

In practice, fizioterapio can refer to:

• physiotherapy as a treatment type
• a period or course of physiotherapy
• physiotherapy sessions in general

So in this sentence, it most likely means something like:

• We will begin physiotherapy treatment
• We will start a course of physiotherapy

The exact nuance comes from the situation, not from the grammar alone.

Yes, that is close to the structure of the Esperanto, but it is not the most natural English.

A very literal breakdown is:

• Ni = we
• komencos = will begin
• fizioterapion = physiotherapy
• krom se = except if / unless
• la kuracisto = the doctor
• diros = will say
• ne = no

So literally:
We will begin physiotherapy, except if the doctor will say no.

But natural English would normally be:

• We will start physiotherapy unless the doctor says no.

That difference is mostly about natural English style, not a difference in meaning.

In normal Esperanto, subject pronouns like mi, vi, li, ni are usually stated, so Ni is expected here.

• Ni komencos... = We will start...

Unlike Spanish or Italian, Esperanto does not normally drop the subject pronoun just because the verb ending already shows the person.

So omitting Ni would usually sound incomplete unless the context were very special, such as notes, headlines, or very informal shorthand.

Then the tense would change.

For example:

• Ni komencos fizioterapion, krom se la kuracisto jam diris ne. = We will start physiotherapy, unless the doctor has already said no.

Or, if the refusal definitely happened:

• Ni ne komencos fizioterapion, ĉar la kuracisto diris ne. = We will not start physiotherapy, because the doctor said no.

So the original sentence uses future tense because the doctor’s decision is still being treated as something not yet settled.