why is there a "se" in this sentence?
I am just starting to get a grasp on direct object pronouns and indirect object pronouns, but I can't quite figure out where this "se" comes into play. Is it the "impersonal se"? I don't think its a DOP or IDOP since it is neither lo, la, or le. Also, the reference article here on the "impersonal se" says that when the impersonal se is used, there is no subject in the sentence, while the following sentence does have a subject. My Colombian roommate isn't able to explain it, he says "it's just there" lol.
Thanks!
Cual es la herramienta que se utilizara en UNASUR para la solucion de conflictos latinoamericanos?
5 Answers
A simpler approach to understanding this is to consider that while "utilizar" normally requires an user (the subject) and something to be used (an object), "se" restricts the focus to just element: either the subject himself/herself/itself, or an external indefinite subject. In this case, a tool cannot be using itself, so a passive interpretation (i.e. a hidden active subject) is more likely: "A tool will be used..."
Think of it this way:
What is the tool that will be used in UNASUR...
It is a passive se here. There is no DOP/IOP/impersonal se here. The impersonal se is nearly identical to passive and in a lot of cases it's exactly the same, but you can tell them part from context. If it was an impersonal se here, one would read it as:
What is the tool that one will use in UNASUR...
and obviously, that's not what the sentence is trying to say.
Here's a quick explanation of passive voice using se:
(Active) Yo tiro la bola / I throw the ball.
(Passive) La bola se tira / The ball is thrown.
Note: tirar agrees with la bola
What the passive voice does is remove the agent of the action - in other words, who does it. In the active voice version, the reader knows that I, the agent, throw the ball. However, in the second sentence in passive voice, all the reader can discern is that the ball is thrown. The agent is not specified.
You have to use context to figure out if it's passive se or impersonal se. Usually it's very obvious. Also, the impersonal se is always in the verb's usted form, whereas passive voice agrees with whatever is the target of the action.
Hope I wasn't too confusing
There is a subject for "se utilizara" but it sort of isn't a "real" subject in that it is not an agent. There, herramienta is really the direct object of the verb that has been promoted to the subject for "se". There technically is a subject, but there is no AGENT to the action. In other words, we don't know who is using the tool, but we know that the tool is the subject of the sentence. It can best be translate by passive in that instance: "will be used."
Heidita has converted one of Lazarus1907's replies to a Reference page called "Transitive and intransitive constructions: use of 'se' "> You can find it here ----> Trans/Intrans/"se".
Here is part of Item 9) from that page:
Many Spanish verbs are transitive, i.e. they need a direct object. For example:
'romper' = to break (something)
'hundir' = to sink (something)
'quemar' = to burn (something)
These transitive verbs assume that there is something or someone (an object) upon which the action is applied, so if you say "el barco hundió" (the ship sunk), you cannot assume that the ship just couldn't float anymore, since the verb is transitive. The sentence is incomplete in Spanish because after hearing "The ship sunk", any native would be expecting an object, i.e. something to sink. So, the ship sunk... another ship perhaps? Without an object, the sentence sounds incomplete and makes no sense. Spanish's solution for this is add an extra "se" that turns the verb into intransitive, so no object is expected, and everything is assumed to be related to the subject. For example, "El barco se hundió" would be "The ship sunk", but this time, the "se" tells us that this ship is not sinking other ships or anything else, but it is just sinking, nothing more.
The verb "preocupar" requires someone to make worried (the object). You can make your parents worried (preocupar a tus madres), and things can make you worried (la situación me preocupa). However, if you are just worried, with no object (no one to make worried), then Spanish resorts to this "se".
Me preocupo
Te preocupas
Se preocupa
Nos preocupamos
Os preocupáis
Se preocupan
This "se" has no translation in English, since "worry" can be used as intransitive in English, but "preocupar" cannot without this pronoun.
This "se" is generally called "pronominal", and more intuitively, intransitivizer "se" by other authors.
¿¿Does this part of Lazarus' information apply to this question today by Halofan00??
¿Cuál es la herramienta que se utilizará en UNASUR para la solucion de conflictos latinoamericanos?
= What tool is going to be used in UNASUR for the resolution of Latin American conflicts?
I believe that the passive se is being used here with utilizará to mean is going to be used/will be used The passive se is used in constructiosn with the verb ser
Utilizará is from the verb utilizar = to use but here it is in the future tense
I am open to correcction on this as I am interested in learning 
