In Spanish there are two verbs that mean "to be" something.   Because there are two different verbs meaning the same thing there are of course different reasons to use each verb.    Generally you would use the verb "ser" to describe things that are permanent and "estar" for things that are temporary.  For example "Yo soy alto" ,  "I am tall", because that is a permanent thing.  "Yo estoy triste", "I am sad" because that is a temporary thing.  However it will be worthwhile to look over the various times to use "ser" and "estar".

Ser To Be Estar
soy I am estoy
eres You are estás
es He/She is está
somos We are estamos
sois They are estáis
son You are están

Use of the verb "SER"

To identify the subject by linking it to a noun or pronoun
Ella es ingeniera. She is an engineer.
Ese animal es vaca. This animal is a cow.
To indicate origin
¿De dónde eres? Where are you from?
Soy de Montville. I am from Montville.
To indicate what something is made of
La alfombra es de lana y las cortinas son de algodón. The carpet is made of wool, and the curtains are made of cotton.

Note: In the first phrase you use "es" because there is one thing.  You are saying "she is" (referring to the carpet).  In the second phrase you use "son" because there are more than one thing.  You are saying "they are".

To indicate possession/ownership
La mochila es de Miguel. It is Miguel's backpack.
¿De quién es el estéreo? Whose stereo is it?
To indicate destination or recipient with para (for)
¿Para quién son las flores? Who are the flowers for?
Son para mi mama. They are for my mother.
To indicate time of day or other time expression
Es la una y media. It is one thirty.
Ya es tarde. It is already late.
To indicate when or where something takes place
El concierto es a las ocho. The concert is at eight.
La junta es en el auditorio. The meeting is in the auditorium.
With adjectives to describe qualities or characteristics that are permanent or basic to the individual or object described
Es una casa muy grande. It is a large house.
Las fresas son rojas. Strawberries are red.
El hielo es frío. Ice is cold.

Use of the verb "ESTAR"

To indicate location
Estamos en el consultorio. We are in the doctor's office.
Fenway Park está en Boston. Fenway park is in Boston.
To indicate a state or condition (usually temporary) of a person or thing, usually resulting from a change
¿Estás enfermo?  No, estoy aburrido. Are you sick?  No, I am bored.
El dictator está muerto. The dictator is dead.

Note:  Although death is permanent, the fact that you are indicating that there was a change in the dictator's condition (from alive to dead) is the reason for using "está" and not "es".

With adjectives to remark on a condition or state that merits a comment, is unexpected, causes surprise, or represents a change from the norm
¡Está grande tu casa! Your house is really big!

Note: You are not remarking about the fact that the house is large (which is a permanent thing), but that you are surprised that the house is so large.

Comparison of "Ser" and "Estar"

¿Cómo son tus padres? What are your parents like?
¿Cómo están tus padres? How are your parents?

In the first sentence you are asking about something that is permanent.  In the second sentence you are asking what condition they are in (are they sick, are they well?)

Es muy nervioso. He is very nervous ( a nervous person).
Está muy nervioso. He is very nervous (about something).
Es un profesor aburrido. He is a boring professor.
El estudiante está aburrido. The student is bored.

Some words change their meaning depending on whether they are used with ser or estar.

    With ser   With estar
aburrido   boring   bored
divertido   amusing   amused
enfermo   sickly   sick
triste   dull   sad
vivo   lively   alive

 Practice Verb Conjugation
Review Uses of SER and ESTAR
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