Marlenie is a university student in Texas. Here she introduces herself and her favorite building on campus.
¡Hola! Yo soy Marlenie. Yo soy tu guía (your guide). Yo soy tu compañera en la clase de español. Este es el edificio (building) académico.
In this introduction, Marlenie uses the verb ser in the first person to talk about herself. A verb is a word that describes an action (e.g., write, eat, etc.) or a state of being (e.g., feel, is, etc.). In Spanish, verbs have different forms, conjugaciones (conjugations), depending on who or what is doing an action, which are called the subjects of the verb.
A subject can be expressed through a noun (a person, animal, or thing; e.g., Sean, Marlenie, the dog, the car, etc.) or a pronoun (e.g., I, he, they, etc.).
The pronouns that indicate who is doing an action are called subject pronouns. Subject pronouns in Spanish are both similar to and different from English. For example, like in English, subject pronouns have singular and plural forms, but, unlike English, some of the pronouns have gender (feminine and masculine). Have a look at this table and compare subject pronouns in both languages. What other similarities/differences do you notice?
| Number | Subject pronouns in Spanish | Subject pronouns in English |
| Singular | yo | I |
| tú | you (informal) | |
| vos | you (informal). Used predominantly in Argentina and Uruguay, but also in other South and Central American countries. More information. | |
| usted/Ud. | you (formal) | |
| él/ella | he/she | |
| Plural | nosotros (masc.)/nosotras (fem.) | we |
| vosotros (masc.)/vosotras (fem.) | you (plural; informal–only used in Spain) | |
| ustedes/Uds. | you (plural: Both informal and formal in Latin America; formal in Spain) | |
| ellos (masc.)/ellas (fem.) | they |
One important difference between Spanish and English is that, while subject pronouns are obligatory in English, they are not needed in Spanish unless there is confusion with respect to who is doing the action, or you want to emphasize the subject. Why do you think this is the case? Have a look at the next table. Pay attention to the different conjugaciones (conjugations) of ser. What do you notice?
| Number | Subject pronoun | Forms of “ser” | |
| Singular | yo | soy | I am |
| tú | eres | you are (informal) | |
| vos | sos | you are (informal). Used predominantly in Argentina and Uruguay, but also in other South and Central American countries. More information. | |
| usted/Ud. | es | you are (formal) | |
| él/ella | es | he/she is | |
| Plural | nosotros (masc.)/nosotras (fem.) | Somos | we are |
| vosotros (masc.)/vosotras (fem.) | sois | you are (plural; informal–only used in Spain) | |
| ustedes/Uds. | son | you are (plural: Both informal and formal in Latin America; formal in Spain) | |
| ellos (masc.)/ellas (fem.) | son | they are |
You can use these forms of the verb ser (to be) to introduce and describe yourself (what you are like, where you are from) and others, and also to describe things/animals/places. For example, when Marlenie talks about her friends, she says:
Efraín es carismático y activo. (Él) es de Killeen, Tejas.
Ellas son Bailey y Carolina. (Ellas) son responsables y estudiosas.
If you want to use ser in a negative sentence, it is super easy! Just place the word no before the conjugated verb:
Efraín no es carismático y activo.
Bailey y Carolina no son responsables.
