"I am going to assume that it is."
Translation:Voy a asumir que lo es.
I believe the use of lo is purely idiomatic and not required by any rule of grammar. In other words, I believe Spanish doesn't require an "it" here any more than English does. However, it may sound better to include lo and that may be something we should be learning.
The "lo" is still an object pronoun, which is implicit in the English sentence. The phrase "lo es" means "it is (something)," with "lo" being an explicit reference back to a something stated earlier or clearly understood by all parties. For example:
That book she gave you is yours to keep, right?
I'm going to assume it is (mine to keep).
In the above exchange, "lo" would represent the parenthetical bit. I assume it would sound incomplete to a native Spanish speaker if you left "lo" out.
The correct way to speak Spanish is to say the words in the right sequence, lo es.
- Es lo. ❌
Incorrect Spanish because the word sequence creates an incorrect sentence. On the other hand, if you have something entirely different that you want to say in Spanish instead of lo es, then it would be possible for you to combine some additional Spanish words with these same two Spanish words spoken in the sequence, es lo, as long as you were careful not to finish the Spanish sentence with the word, lo.
The "Lo" here is really necessary, otherwise the Spanish sounds wrong. Here is an explanation from the web to illustrate this. Using Lo With Ser and Estar It is common when answering questions to use lo before the verbs for "to be" to refer to a preceding noun or adjective. When used in this way, lo has neither number nor gender. —¿Es nueva tu computadora?. —No lo es. ("Is your computer new?" "It isn't.") —¿Estaban felices? —Sí, lo estaban. ("Were they happy?" "Yes, they were.")
I went looking for your reference and found this: https://www.thoughtco.com/using-lo-spanish-3079438 I think everyone who came to this forum thread with questions would benefit from this link.
Yes, ThoughtCo provides a lot of really good usage information. However, they are incorrect to describe "lo" as a subject pronoun and, unfortunately, the exact section that ostensibly applies to this Duo sentence is wrong.
The direct object pronoun "lo" is never a subject pronoun. Perhaps, people are interpreting the "lo" as if it was a subject pronoun in order to make the Spanish expression match the English, but that desire to match up the two constructions doesn't turn object pronouns into subject pronouns.
When someone answers "no lo es" in response to a simple question, the "lo" is not the "it" in the English phrase "no it isn't." In fact, Spanish never explicitly includes that "it." While English does include the subject pronoun, Spanish does not. On the other hand, Spanish does usually include the object pronoun, while English rarely does, This is a very fundamental difference between the two languages - that is, Spanish likes object pronouns and English likes subject pronouns.
I should think it would be - eso lo es, unless you were leaving "it" as implied. In this sentence, the phrase que lo es means "that it is (it)." The last "it" is implied in English, but is represented by lo in the Spanish. Also, the "that" is really a conjunction and is part of the "assume that" phrase.
But, "lo que es " is very different from "que lo es." That is, you can't use the two phrases interchangeably and expect the meaning to be the same. And for that reason, you can't use "lo que es " as a translation of "that it is."
- "voy a asumir lo que es" = "I'm going to assume WHAT (someone/something) is"
- "voy a asumir que eso es" = "I'm going to assume (that) that is (something)"
The "lo " only appears to be in the subject location because the subject has been omitted. It's actually a "proclitic" Spanish construction in which the direct object pronoun is always placed immediately before the verb.
Given the original English sentence we are to translate, I see no grammatical reason to include "lo." However, its inclusion by Duo suggests it is idiomatic or used to make the statement a little more emphatic. In either case, including "lo " seems common enough in this particular phrase (you can easily find a lot of examples on the web) that it seems worth emulating.