—¿Quién toma fotos? —Margarita las toma. incorrect —David, ¿estás usando la computadora? —No, ahora no. You answeredNo voy a usarla más tarde (later on). correct —Quiero ver el hotel donde vamos a quedarnos (stay). —Lo siento, no lo puedes ver ahora. incorrect —¿Nos entienden ustedes? —Sí, You answeredte entienden. correct —¿Dónde está Ana leyendo el libro? —Está leyéndolo al lado de la piscina.

Margarita las toma.

La voy a usar más tarde.

No lo puedes verlo ahora.

Sí, los entendemos.

Lo está leyendo al lado de la piscina.

Explanation:

It is called a direct object (in traditional grammar, direct complement) to the function played by a syntactic constituent (phrase, pronoun or a substantive subordinate proposition), different from the grammatical subject, which is necessarily required by a transitive verb

It is the person or object on which the action expressed by the verb falls, it is a modifier of the predicate. The direct object can be expressed by pronouns: lo, la, los, las. Substituting the direct object of a sentence for one of these pronouns is a recommended way to verify that it is indeed the direct object.