Ser and Estar
There are two verbs in Spanish that are equivalent to the English word "to be," namely ser and estar. Unfortunately, they are not interchangeable at random for Spanish learners. The distinction between the two verbs is, however, very clear in principle.

Ser is used to categorise its subject (e.g. Juan is médico ‘Juan is a doctor,' El suelo es de madera ‘The floor is made of wood'), whereas estar is used to ascribe acquired properties (e.g. El suelo está sucio ‘The floor is unclean,' Manolo está en el jardn ‘Manolo is in the garden’)

It is possible to recognise those circumstances that need one or both of the verbs as a starting point for learning how to utilise them.

Verb conjugation tables for ser and estar: Imperative Form

PERSON	SUBJECT	PRESENT		FUTURE
		SER	ESTAR	SER	ESTAR
Singular
1st person	yo (I)	soy	estoy	seré	estaré
2nd person	tú (you)	eres	estás	serás	estarás
3rd person	usted, él, ella (he/ she)	es	está	será	estará
Plural
1st person	yo (I)	somos	estamos	seremos	estaremos
2nd person	tú (you)	sois	estáis	seréis	estaréis
3rd person	usted, él, ella (he/ she)	son	están	serán	estarán

Situations which demand ser
Ser is used to talk about permanent or lasting attributes. Let's take a look on the below situations.

A. When the verb ‘to be’ links the subject to a noun, pronoun or infinitive:

Example

SPANISH	ENGLISH
(El) Perú es una república.	Peru is a republic.
Soy el nuevo jefe.	I am the new boss.
Este es el mío.	This is mine.
Yo soy alta, morena, y delgada.	I am tall, dark-skinned, and thin.

B. Ser to indicate the origin of persons or things

Example

SPANISH	ENGLISH
Mi madre es de Malasia.	My mother is from Malaysia.
Joan es andaluz.	Joan is Andalusian.
He is from a rich family.	Es de una familia rica.

C. Ser to indicate ownership or possession

Example

SPANISH	ENGLISH
La bufanda es de lana.	The scarf is made of wool.

D. Ser in mathematical calculations

Example

SPANISH	ENGLISH
Tres y cinco son ocho.	Three plus five makes eight.

E. Ser to refer to the time of day, date or seasons

Example

SPANISH	ENGLISH
Es la una.	It is one o’clock.
Fue el 18 de abril.	It was the 14th of April.
Es verano.	It's summer.

F. Ser to state where something happens or the location of events

Example

SPANISH	ENGLISH
La cena será en el restaurante japonés.	The dinner will be at the Japanese restaurant.
Aquí es donde se estudia.	This is where he studies.

Situations which demand estar
Estar is used to indicate temporary states and locations. Let's take a look on the below situations.

A. To express location or position (whether temporary or permanent)

Example

SPANISH	ENGLISH
Sus papeles estaban sobre la mesa.	His papers were on the table.
Lima está en (el) Perú.	Lima is in Peru.

Ser and estar with adjectives
It is possible to use either ser or estar with adjectives, but not indiscriminately. If the following distinctions are borne in mind, the context of use should indicate which is the correct verb to choose.

A. Ser + adjective
Ser + adjective in general indicates an inherent or essential characteristic, with no idea of change. It implies that you are putting someone or something into a particular class or type. It is ‘to be’ by nature:

B. Estar + adjective
Estar + an adjective frequently denotes an accidental or temporary state. It is ‘to be’ by condition:

Example

Ser + adjective	Estar + adjective
Ana es pálida. Ana is pale (normally of pale complexion).	Ana está pálida. Ana is pale (has turned pale).
Estas peras son agrias. These pears are sour (of a sour variety).	Estas peras están agrias. These pears are sour (because they are unripe).
Mi hermano es alegre. My brother is happy (of cheerful disposition).	Mi hermano está alegre. My brother is happy (in a happy state of mind).

It is important to realize that this construction indicates a condition that is not only susceptible or likely to change, but also the result of a change:

SPANISH	ENGLISH
Está vivo.	He is alive.
Está muerto.	He is dead.
Está calvo.	He is bald.

Adjectives which change their meaning with ser or estar
NOTE! The above is not intended to be a complete list, but serves to reinforce the general distinctions made between ser and estar.

	SER	ESTAR
cansado	tiresome, tiring	tired
listo	clever	ready
malo	bad	ill
bueno	good	well, tasty (food)
vivo	lively, clever	alive
aburrido	boring	bored
divertido	amusing	amused
fresco	cheeky	cool (e.g.a drink)
consciente	aware	conscious [SP]
rico	rich	tasty [SP]