En conclusión, la mayoría está de acuerdo.

En conclusión is a very common linking phrase meaning in conclusion or to sum up. It is used to introduce a final summary or result.

In this sentence, it tells you that the speaker is wrapping up what has been said before.

Other similar expressions are:

• En resumen = in summary
• Para concluir = to conclude
• En definitiva = all in all / ultimately

The comma after En conclusión is normal, because it is being used as an introductory phrase.

La mayoría means the majority or most people / most of them, depending on context.

Literally, it is a noun phrase:

• la = the
• mayoría = majority

So la mayoría is grammatically a singular noun phrase, even though its meaning refers to a group of people.

For example:

• La mayoría está de acuerdo. = The majority agrees / Most people agree.
• La mayoría votó a favor. = The majority voted in favour.

This is one of the most common questions learners ask.

The subject here is la mayoría, which is grammatically singular, so the verb is also singular:

• La mayoría está de acuerdo.

Even though it refers to many people, the head noun is mayoría, not the people inside the group.

This is the standard structure in Spanish.

Compare:

• La mayoría está cansada.
• La gente está contenta.

Both mayoría and gente refer to multiple people, but they usually take a singular verb because the noun itself is singular.

In standard Spanish, especially in careful writing, la mayoría está de acuerdo is preferred because mayoría is singular.

However, in real speech, some native speakers may sometimes use a plural verb when they are thinking more about the people than about the collective noun. Even so, for learners, the safest and most standard choice is:

• La mayoría está de acuerdo.

If you want a clearly plural subject, you can say:

• La mayoría de las personas están de acuerdo.

Here, the plural idea is more visible because of las personas, and plural agreement is more likely to appear.

But with just la mayoría, use está.

Because estar de acuerdo is a fixed expression meaning to agree or to be in agreement.

So:

• estar de acuerdo = to agree
• no estar de acuerdo = to disagree

You cannot normally drop de here.

Examples:

• Estoy de acuerdo. = I agree.
• ¿Estás de acuerdo? = Do you agree?
• No estamos de acuerdo. = We do not agree.

Think of de acuerdo as a set phrase that goes with estar.

Because the expression is estar de acuerdo, not ser de acuerdo.

In this case, estar does not mean just a temporary physical state. It is simply the verb used in the idiom.

So you say:

• Estoy de acuerdo.
• Estamos de acuerdo.

But not:

• Soy de acuerdo
• Es de acuerdo

Learners often try to analyse ser vs estar by general rules, but some expressions must simply be learned as complete chunks. Estar de acuerdo is one of them.

They are related, but they are not the same thing.

• estar de acuerdo = to agree
• acordar = to agree on something, arrange, decide, or remember in some contexts

Examples:

• Estamos de acuerdo. = We agree.
• Acordamos la fecha. = We agreed on the date.
• Acordaron reunirse mañana. = They agreed to meet tomorrow.

So in your sentence, de acuerdo is not a verb form. It is part of the expression estar de acuerdo.

Because de acuerdo can be used in different ways depending on what follows.

If you simply mean someone agrees, you can stop at de acuerdo:

• La mayoría está de acuerdo.
• Estoy de acuerdo.

If you want to say agree with someone, you usually add con:

• Estoy de acuerdo con Ana.
• No estamos de acuerdo con el profesor.

If you want to say agree about / on something, Spanish often uses en:

• Estamos de acuerdo en eso.
• Todos estamos de acuerdo en que es una buena idea.

So your sentence is complete without con because it just states general agreement.

No, that would sound wrong in normal Spanish.

You need the article:

• La mayoría está de acuerdo.

Spanish usually uses the definite article with abstract or collective nouns in this kind of structure.

You can also expand it:

• La mayoría de los estudiantes está de acuerdo.
• La mayoría del grupo está de acuerdo.

But mayoría by itself without la is not natural here.

A very common way is:

• La mayoría de la gente está de acuerdo.
• La mayoría de las personas está de acuerdo.

Both are fine.

You can also specify a group:

• La mayoría de los estudiantes está de acuerdo.
• La mayoría de los votantes está de acuerdo.

This helps if you want to make clear who the majority refers to.

Yes. If you say what group the majority belongs to, you normally use:

• la mayoría de + noun

Examples:

• La mayoría de los alumnos está de acuerdo.
• La mayoría de mis amigos está de acuerdo.
• La mayoría del público está de acuerdo.

This is a very useful pattern to learn.

In Spain, mayoría is pronounced approximately like:

• ma-yo-RÍ-a

The stress is on rí because of the written accent: mayoría.

A rough English-friendly guide would be:

• mah-yo-REE-ah

Also, in most of Spain, the c in conclusión is pronounced with the th sound of think before i or e:

• con-clu-thyón in much of Spain

But in Latin America and in some parts of Spain, you may hear an s sound instead.

Both words have written accents to show where the stress falls.

• conclusión → stress on the final syllable -sión
• mayoría → stress on -rí-

These accent marks are important because they affect pronunciation.

Without the accent, a learner might stress the wrong syllable.

So:

• con-clu-SIÓN
• ma-yo-RÍ-a

Usually it goes at the beginning when it introduces a final statement:

• En conclusión, la mayoría está de acuerdo.

That is the most natural placement.

You could sometimes move similar linking phrases around for style, but for learners, the sentence-initial position is best and most standard.

So if you want to sound natural and clear, keep it at the front.

It sounds neutral to slightly formal because of En conclusión.

• En conclusión is common in writing, presentations, essays, reports, and structured speech.
• La mayoría está de acuerdo itself is neutral and can be used in many contexts.

In more casual speech, someone might simply say:

• Al final, la mayoría está de acuerdo.
• En resumen, la mayoría está de acuerdo.
• Total, la mayoría está de acuerdo. (more colloquial in some contexts)

So the full sentence feels clear, correct, and suitable for formal or semi-formal communication.