Ser Vs Estar


One of the most common verbs in spanish is an irregular verb called "ser". Here are the present-tense conjugations for "ser":

Yo soy

Tú eres

El/Ella/Usted es

Nosotros somos

Vosotros sois

Ellos/Ellas/Ustedes son

Both "ser" and "estar" mean "to be", but they are used in different contexts.

"Estar" is used for:

Location

Nosotros estamos en Costa Rica. (We are in Costa Rica)

Las toallas estan en el bano. (The towels are in the bathroom.)

When a verb is in progress

Tú estas estudiando espanol (You are studying Spanish.)

El bebe esta llorando (The baby is crying)

"Ser" is used for:

When a noun is describing another noun

Ellos son bomberos (They are firefighters)

Yo soy un doctor (I am a doctor.)

Time

Hoy es lunes (Today is monday.)

Manana es martes (Tomorrow is Tuesday.)

Origin

El coche es de Alemania (The car is from Germany.)

Tú eres de Florida. (You are from Florida.)

Saying what something is made out of

La mesa es de madera (The table is wooden.)

El anillo es hecho de oro (The ring is made from gold.)

Posession

El libro es de Maria (The book belongs to Maria.)

El perro es de mi amigo (The dog belongs to my friend.)

Using "ser" and "estar" with adjectives

"estar" is used when the adjective is temporary, while "ser" is used when the adjective is permanent or long-lasting

El semaforo esta rojo (The traffic light is red.)

El coche es rojo (The car is red.)

The color of a traffic light is temporary because it changes frequently. In contrast, the color of a car is permanent or long-lasting because it does not change frequently. It's very common for traffic lights to change color but it's not common for cars to change color.

Let's take a look at sentences that use "ser" or "estar" with an adjective:

El cafe esta caliente. (The coffee is hot.)
The high temperature of the coffee is temporary, so "estar" is used.

Ella es alta. (She is tall)
A person's height does not change very often, so "ser" is used.

Estoy nervioso. (I'm nervous.)
Emotions change frequently, so "estar" is used

Su casa es grande (His house is big.)
The size of a house does not change frequently, so "ser" is used

El cielo esta nublado. (The sky is cloudy.)
The sky frequenlty changes from cloudy to sunny, so "estar" is used.

Robar es malo. (Stealing is bad.)
Stealing is always bad, so "ser" is used.