At a minimum, sentences consist of subjects (a person, place, or thing) and verbs (actions). When the verb is in its base or unchanged form, it is called the “infinitive”: to be, to run, to jump. In sentences, infinitives undergo changes.
In English, we don’t say:
*I to be tall or *They to be nice (* = non-standard).
When we make sentences with verbs, the verb changes, or is conjugated so that the subject and verb match. In fact, what we do say is:
I am tall or They are nice
The verb “to be” is conjugated (changed) so that it matches with the subjects “I” and “they”.
Likewise, the infinitives of verbs in Spanish are conjugated when we make full sentences. The infinitive “to be” is “Ser” and it is conjugated, or changed when forming sentences:
|(yo) soy||I am||(nosotros) somos||We are|
|(tú) eres||You are (sg, fam)||(vosotros) sois||You are (pl, Spain)|
|(él) es||He is||(ellos) son||They are|
|(ella) es||She is||(ellas) son||They are (fem)|
|Ud. es||You are (sg, form)||(Uds.) son||You are (pl, L.Am)|
In the chart above, the subject pronouns (yo, tú, él, ella, Ud., nosotros, vosotros, ellos, ellas, Uds.) are in parentheses. This is to introduce the idea that subject pronouns are not necessary when conjugating verbs in Spanish. For example:
|Yo soy||I am||Tú eres||you are|
|Soy||I am||Eres||you are|
Both “yo soy” and just “soy” mean “I am”, and both “tú eres” and just “eres” mean “you are”. We will return to this idea when we get to more verb conjugations.
Examples with the verb SER conjugated:
|Soy alto.||I am tall.|
|Originalmente, soy de Oregon.||Originally, I’m from Oregon.|
We could also use the subject pronoun “yo” (I) and say:
|Yo soy alto.||I am tall.|
|Originalmente yo soy de Oregon.||Originally, I’m from Oregon.|
|Él es mi amigo.||He’s my friend.|
OJO (notice): to make a sentence negative, put “no” in front of the verb.
|Ella no es mi novia.||She is not my girlfriend.|
|Somos de los Estados Unidos.||We’re from the United States.|
|Vosotras sois muy intelegentes.
(vosostros/as = used in Spain)
|You (pural / fem) are very intelligent.|
|Son estudiantes.||They are students.|
Let’s take a look at the last example: “son” is actually ambiguous by itself. Given a context, the statement “son estudiantes” might be the answer given to someone who asked “Who are they?”, pointing to a group of students. But “son estudiantes” could also mean “you guys are students”. If the context is not clear, the subject pronouns (ellos, ellas, Uds.) should be added to clarify:
|Ellos son estudiantes||They are students.|
|Ellas son estudiantes||They are students.
|Uds. son estudiantes||You guys are students.|
Once the subject pronouns are used, there is no ambiguity.