Learn Hardcore Spanish (Spain): La ciudadanía no solo protesta en la manifestación, sino que además cambia sus hábitos diarios para cuidar el planeta. - Citizens not only protest at the demonstration, but also change their daily habits to care for the planet.

la ciudadanía emphasizes the group as a single social body.
In public discourse in Spain (news, politics, institutions), la ciudadanía is very common:
- La ciudadanía exige más transparencia. = The public demands more transparency.

So the sentence is presenting the public as a collective actor that protests and changes habits.

If la ciudadanía refers to many people, why are the verbs singular (protesta, cambia)?

Because ciudadanía is grammatically singular. In Spanish, the verb agrees with the grammatical number of the subject, not its real-world size.

La ciudadanía protesta. → singular subject → protesta (3rd person singular)
Los ciudadanos protestan. → plural subject → protestan (3rd person plural)

Other examples with collective nouns:

La gente está cansada. (not están)
El público aplaude.

Even though they refer to many people, they take singular verbs.

How does no solo ... sino que además ... work? Is it like not only ... but also ... in English?

Yes, it’s the Spanish equivalent of not only ... but also ..., with some small structural differences.

Basic pattern:

no solo
- [first action/idea], sino que además
  - [second action/idea]

In the sentence:

no solo protesta en la manifestación
sino que además cambia sus hábitos diarios

That means:

The citizenry doesn’t just do the first thing (protest); it also does something more (change habits).

Notes:

sino is used after a negation (here, no solo).
que is used because what follows is a full clause with a verb (cambia).
además adds the meaning in addition / furthermore and emphasizes the extra effort.

You could also say:

La ciudadanía no solo protesta en la manifestación, sino que cambia sus hábitos diarios.
(Perfectly correct, just slightly less emphatic without además.)

Why sino and not pero in no solo protesta..., sino que además cambia...?

Sino and pero both translate roughly as but, but they are used differently.

pero introduces simple contrast or addition:
- Protesta, pero no cambia sus hábitos. = It protests, but it doesn’t change its habits.
sino is used after a negation to correct, replace, or add a second, “better” or “true” option:
- No protesta, sino que cambia sus hábitos.
- No solo protesta, sino que además cambia sus hábitos.

With no solo ... sino (que), the meaning is not only X, but also Y, which Spanish treats as a special pattern using sino, not pero.

Why is there a que after sino here? Can I say sino además cambia without que?

In standard Spanish:

Use sino when the second part is just a word or phrase (no new conjugated verb):
- No quiere café, sino té.
- No vino en coche, sino en tren.
Use sino que when the second part has a conjugated verb (a full clause):
- No quiere que vengas tú, sino que vaya yo.
- No solo protesta, sino que además cambia sus hábitos.

Here, cambia is a conjugated verb, so you use sino que.

You will hear some native speakers drop que in fast speech, but in careful and written Spanish, with a full clause, sino que is the recommended form.

What exactly does además mean here, and is it necessary?

Además means also / furthermore / in addition.

In this sentence it:

Emphasizes that the second action (cambia sus hábitos diarios) is another extra effort on top of protesting.
Makes the structure parallel to English not only..., but also... or even not only..., but moreover...

Is it necessary?

Grammatically: No.
- La ciudadanía no solo protesta en la manifestación, sino que cambia sus hábitos diarios... is fully correct.
Stylistically: además adds emphasis and a sense of “going further”.

Why is it en la manifestación and not a la manifestación?

Because the preposition depends on the verb and meaning:

ir a la manifestación = to go to the protest (direction / destination → a)
protestar en la manifestación = to protest at / during the protest (location / setting → en)

Here, the focus is not on going somewhere but on where the protest action happens, so Spanish uses en (in/at):

Manifestar(se) en la calle
Hablar en la reunión
Cantar en el concierto

Also, la manifestación (with la) suggests a specific protest previously known from context, not just any random one.

Why la manifestación and not una manifestación?

The choice between la and una is similar to the vs a in English:

la manifestación = the demonstration (a specific one the speaker and listener can identify or that has been mentioned or is obvious from context)
una manifestación = a demonstration (any protest, not specified)

In this kind of example sentence, using la manifestación often implies:

“at the demonstration” in general, as a known type of public event,
or
a particular demonstration everyone is talking about (for example, a big climate march).

Depending on the broader context, una manifestación could also be correct, but it would sound more like “at a demonstration (one of many).”

Why sus hábitos diarios and not los hábitos diarios?

Both could be grammatically correct, but there is a nuance:

sus hábitos diarios = their daily habits (clearly refers to the citizenry’s own habits)
los hábitos diarios = the daily habits (more general, could be interpreted as daily habits in general, not necessarily those of the citizenry)

Using sus makes it explicit that:

The citizenry changes its own habits, not just some abstract set of habits.
The subject of the sentence (la ciudadanía) is personally involved and responsible.

Why is diarios placed after hábitos? Could I say diarios hábitos?

In Spanish, most descriptive adjectives normally go after the noun:

hábitos diarios = daily habits
comida saludable = healthy food
ropa limpia = clean clothes

Putting diarios before hábitos (diarios hábitos) would sound strange or poetic and is not normal in everyday Spanish.

So the natural order is:

sus hábitos diarios = their daily habits

Why is it para cuidar el planeta and not para que cuida el planeta?

Para + infinitive and para que + subjunctive are two different structures:

para + infinitive (same subject in both actions)
- The subject of the main verb and the infinitive is the same:
  - La ciudadanía cambia sus hábitos para cuidar el planeta.
    → The citizenry changes (subject) in order to care (same subject) for the planet.
para que + subjunctive (different subjects)
- Use this when the subject of the second verb is different:
  - La ciudadanía cambia sus hábitos para que el gobierno reduzca la contaminación.
    → The citizenry changes its habits so that the government reduces pollution.

So in your sentence:

The same subject (la ciudadanía) both cambia and cuida, so para cuidar (infinitive) is correct.
para que cuida el planeta is ungrammatical; with para que, you would need the subjunctive and usually a different subject: para que se cuide el planeta, para que todos cuiden el planeta, etc.

Why don’t we say para cuidar al planeta? When do we use a / al?

Al = a + el. The preposition a is used:

For direction / destination:
- Voy al parque.
For the personal a (before direct objects that are specific people or loved animals):
- Ayudo a mi madre.
- Quiero a mi perro.

El planeta here is a thing, not a person or pet, so Spanish normally does not use the personal a:

cuidar el planeta = to take care of the planet

You would use al only if planeta were the indirect object or a location you move towards, which it is not here. So para cuidar el planeta is the correct form.