Ella está viva y tranquila.

Because Spanish usually uses estar for states or conditions, especially ones that can change, while ser is used more for essential characteristics.

So:

• Ella está viva = she is alive
• Ella está tranquila = she is calm / peaceful

Even though being alive may sound permanent in English, Spanish normally says estar vivo/a, not ser vivo/a, when talking about a person being alive.

They agree with ella, which is feminine singular.

In Spanish, adjectives usually change to match the gender and number of the noun or pronoun they describe:

• él está vivo y tranquilo
• ella está viva y tranquila
• ellos están vivos y tranquilos
• ellas están vivas y tranquilas

So the -a ending is there because the sentence is about a female person.

Yes, you could absolutely say Está viva y tranquila.

Spanish often drops subject pronouns because the verb ending already tells you who the subject is. In está, the form shows it is he/she/it/you (formal).

You use ella when you want to:

• make the subject clear
• add emphasis
• contrast with someone else

For example:

• Ella está viva y tranquila, pero él está herido.

So ella is correct, but often optional.

The accent mark shows where the stress goes: es-TÁ.

It also helps distinguish forms in writing. Without the accent, esta usually means:

• this (feminine), as in esta casa

With the accent:

• está = is from estar

So the accent matters both for pronunciation and meaning.

Tranquila can mean things like:

• calm
• peaceful
• relaxed
• not worried
• resting quietly, depending on context

So it does not always mean exactly one English word. In this sentence, it suggests she is in a calm or settled state.

That is very normal in Spanish. The structure is:

• Ella = subject
• está = verb
• viva y tranquila = two linked adjectives

The y simply means and, connecting the two adjectives.

Spanish often uses this pattern:

• Está cansado y enfadado.
• Está feliz y orgullosa.

So viva y tranquila is just alive and calm as a pair of descriptions.

Yes, grammatically that is possible, but the order can affect what sounds most natural or what gets emphasis.

Usually, the adjective placed first may feel a bit more prominent. So:

• viva y tranquila may highlight that she is alive first, then also calm
• tranquila y viva might sound less natural in many contexts, unless you specifically want that order

Both are understandable, but viva y tranquila sounds more natural in many situations.

Yes, it is related to vivir (to live).

Vivo/viva means alive.

Pronunciation in Spain is approximately:

• viva → BEE-bah
• tranquila → trahn-KEE-lah

A few notes for Spain Spanish:

• v and b are pronounced very similarly
• qu before i sounds like k
• the ll in ella is usually pronounced like the y in yes in much of Spain

So Ella está viva y tranquila sounds roughly like:

EH-ya es-TA BEE-ba ee trahn-KEE-la

Yes. Viva can have other uses depending on context.

For example:

• as an adjective: una mujer viva can mean a lively / sharp / spirited woman in some contexts
• as an exclamation: ¡Viva España! = Long live Spain!

But in Ella está viva, the meaning is clearly alive.

Normally, y means and.

Spanish changes y to e only before words that begin with an i sound:

• padre e hijo
• España e Italia

But here the next word is tranquila, which starts with t, so it stays y:

• viva y tranquila

Not in this meaning.

• está viva = she is alive
• está tranquila = she is calm

If you say es viva, it usually changes the meaning of viva. It can mean something like:

• she is lively
• she is clever / sharp

So Ella es viva y tranquila would not mean the same thing as Ella está viva y tranquila.

The structure is:

• Ella = subject pronoun
• está = 3rd person singular of estar
• viva y tranquila = predicate adjectives joined by y

So the pattern is:

subject + estar + adjective + y + adjective

This is a very common Spanish pattern for describing someone's current state or condition.