Singular or Plural?

Two singular nouns joined by the conjunction o (for "or") can be treated as a singular or plural unit, not just as a singular unit as they must be in English. Some examples:

• Viene(n) Roberto o Teresa. (Roberto or Teresa is coming.)
• El gato o el perro tiene(n) una gran cantidad de beneficios. (The cat or dog offer a great deal of benefits.)
• Buscamos un juguete o un rompecabezas barato(s). (We're looking for a cheap game or puzzle.)

In most cases, either the singular or plural form can be used. However, if the speaker intends to convey the sense that just one of the nouns is applicable, the singular must be used: Viene Roberto o Teresa, pero no los dos. (Robert or Teresa is coming, but not both of them.)

When two singular nouns are joined by ni (usually translated as "neither" or "nor"), the plural form is typically used:

• Ni él ni yo podemos salir. (Neither he nor I can leave.)
• Ni el coche ni el sospechoso fueron localizados. (Neither the car nor the suspect were located.)