Whom vs who
Qué es la diferencia entre los dos palabras?
Please answer in English 
Thanks.
9 Answers
Hola Thierry
Both are relative pronouns (who, whom, that, which, whose) both mean 'quien' or 'que' (only with persons) in Spanish but have slightly different uses.
When the relative pronoun refers to the subject of the sentence 'who' is used, and when it refers to the object 'whom' is used.
My friend who came last night will stay here for a while.
'My friend' here is the subject (the actor, the agent, the one who carries out the action)
My friend whom I called last night is pleased with the offer.
'My friend' here is the object (the acted-upon or the receiver of the action)
I hope that helped.
Many native English speakers get this wrong, especially in question form. Let me first say,
1) You will be forgiven for making a mistake with this. 2) You will hear mistakes being made all of the time by natives.
The most common mistake I hear is with respect to the usage in the question form.
Rather than relying on a rule. This is a good opportunity to just memorize some correct usages.
It may be helpful to memorize "Whom do you know...", so that you get it right.
Correct: "Whom do you know at XYZ Company whom I can call about job opportunities there?"
Incorrect: "Who do you know at XYZ Company who I can call about job opportunities there."
We even have a saying, "It's not what you know, it's who you know." If said correctly, it would be "It's not what you know, it's whom you know.
This may not explain it but it will certainly amuse those of whom are interested.
Abbott: Well Costello, I'm going to New York with you. You know Bucky Harris, the Yankee's manager, gave me a job as coach for as long as you're on the team.
Costello: Look Abbott, if you're the coach, you must know all the players.
Abbott: I certainly do.
Costello: Well you know I've never met the guys. So you'll have to tell me their names, and then I'll know who's playing on the team.
Abbott: Oh, I'll tell you their names, but you know it seems to me they give these ball players now-a-days very peculiar names.
Costello: You mean funny names?
Abbott: Strange names, pet names...like Dizzy Dean...
Costello: His brother Daffy.
Abbott: Daffy Dean...
Costello: And their French cousin.
Abbott: French?
Costello: Goofè.
Abbott: Goofè Dean. Well, let's see, we have on the bags, Who's on first, What's on second, I Don't Know is on third...
Costello: That's what I want to find out.
Abbott: I say Who's on first, What's on second, I Don't Know's on third.
Costello: Are you the manager?
Abbott: Yes.
Costello: You gonna be the coach too?
Abbott: Yes.
Costello: And you don't know the fellows' names?
Abbott: Well I should.
Costello: Well then who's on first?
Abbott: Yes.
Costello: I mean the fellow's name.
Abbott: Who.
Costello: The guy on first.
Abbott: Who.
Costello: The first baseman.
Abbott: Who.
Costello: The guy playing...
Abbott: Who is on first!
Costello: I'm asking YOU who's on first.
Abbott: That's the man's name.
Costello: That's who's name?
Abbott: Yes.
Costello: Well go ahead and tell me.
Abbott: That's it.
Costello: That's who?
Abbott: Yes.
PAUSE
Costello: Look, you gotta first baseman?
Abbott: Certainly.
Costello: Who's playing first?
Abbott: That's right.
Costello: When you pay off the first baseman every month, who gets the money?
Abbott: Every dollar of it.
Costello: All I'm trying to find out is the fellow's name on first base.
Abbott: Who.
Costello: The guy that gets...
Abbott: That's it.
Costello: Who gets the money...
Abbott: He does, every dollar. Sometimes his wife comes down and collects it.
Costello: Whose wife?
Abbott: Yes.
PAUSE
Abbott: What's wrong with that?
Costello: Look, all I wanna know is when you sign up the first baseman, how does he sign his name?
Abbott: Who.
Costello: The guy.
Abbott: Who.
Costello: How does he sign...
Abbott: That's how he signs it.
Costello: Who?
Abbott: Yes.
PAUSE
Costello: All I'm trying to find out is what's the guy's name on first base.
Abbott: No. What is on second base.
Costello: I'm not asking you who's on second.
Abbott: Who's on first.
Costello: One base at a time!
Abbott: Well, don't change the players around.
Costello: I'm not changing nobody!
Abbott: Take it easy, buddy.
Costello: I'm only asking you, who's the guy on first base?
Abbott: That's right.
Costello: Ok.
Abbott: All right.
PAUSE
Costello: What's the guy's name on first base?
Abbott: No. What is on second.
Costello: I'm not asking you who's on second.
Abbott: Who's on first.
Costello: I don't know.
Abbott: He's on third, we're not talking about him.
Costello: Now how did I get on third base?
Abbott: Why you mentioned his name.
Costello: If I mentioned the third baseman's name, who did I say is playing third?
Abbott: No. Who's playing first.
Costello: What's on first?
Abbott: What's on second.
Costello: I don't know.
Abbott: He's on third.
Costello: There I go, back on third again!
PAUSE
Costello: Would you just stay on third base and don't go off it.
Abbott: All right, what do you want to know?
Costello: Now who's playing third base?
Abbott: Why do you insist on putting Who on third base?
Costello: What am I putting on third.
Abbott: No. What is on second.
Costello: You don't want who on second?
Abbott: Who is on first.
Costello: I don't know.
Abbott & Costello Together:Third base!
PAUSE
Costello: Look, you gotta outfield?
Abbott: Sure.
Costello: The left fielder's name?
Abbott: Why.
Costello: I just thought I'd ask you.
Abbott: Well, I just thought I'd tell ya.
Costello: Then tell me who's playing left field.
Abbott: Who's playing first.
Costello: I'm not... stay out of the infield! I want to know what's the guy's name in left field?
Abbott: No, What is on second.
Costello: I'm not asking you who's on second.
Abbott: Who's on first!
Costello: I don't know.
Abbott & Costello Together: Third base!
PAUSE
Costello: The left fielder's name?
Abbott: Why.
Costello: Because!
Abbott: Oh, he's centerfield.
PAUSE
Costello: Look, You gotta pitcher on this team?
Abbott: Sure.
Costello: The pitcher's name?
Abbott: Tomorrow.
Costello: You don't want to tell me today?
Abbott: I'm telling you now.
Costello: Then go ahead.
Abbott: Tomorrow!
Costello: What time?
Abbott: What time what?
Costello: What time tomorrow are you gonna tell me who's pitching?
Abbott: Now listen. Who is not pitching.
Costello: I'll break your arm, you say who's on first! I want to know what's the pitcher's name?
Abbott: What's on second.
Costello: I don't know.
Abbott & Costello Together: Third base!
PAUSE
Costello: Gotta a catcher?
Abbott: Certainly.
Costello: The catcher's name?
Abbott: Today.
Costello: Today, and tomorrow's pitching.
Abbott: Now you've got it.
Costello: All we got is a couple of days on the team.
PAUSE
Costello: You know I'm a catcher too.
Abbott: So they tell me.
Costello: I get behind the plate to do some fancy catching, Tomorrow's pitching on my team and a heavy hitter gets up. Now the heavy hitter bunts the ball. When he bunts the ball, me, being a good catcher, I'm gonna throw the guy out at first base. So I pick up the ball and throw it to who?
Abbott: Now that's the first thing you've said right.
Costello: I don't even know what I'm talking about!
PAUSE
Abbott: That's all you have to do.
Costello: Is to throw the ball to first base.
Abbott: Yes!
Costello: Now who's got it?
Abbott: Naturally.
PAUSE
Costello: Look, if I throw the ball to first base, somebody's gotta get it. Now who has it?
Abbott: Naturally.
Costello: Who?
Abbott: Naturally.
Costello: Naturally?
Abbott: Naturally.
Costello: So I pick up the ball and I throw it to Naturally.
Abbott: No you don't, you throw the ball to Who.
Costello: Naturally.
Abbott: That's different.
Costello: That's what I said.
Abbott: You're not saying it...
Costello: I throw the ball to Naturally.
Abbott: You throw it to Who.
Costello: Naturally.
Abbott: That's it.
Costello: That's what I said!
Abbott: You ask me.
Costello: I throw the ball to who?
Abbott: Naturally.
Costello: Now you ask me.
Abbott: You throw the ball to Who?
Costello: Naturally.
Abbott: That's it.
Costello: Same as you! Same as YOU! I throw the ball to who. Whoever it is drops the ball and the guy runs to second. Who picks up the ball and throws it to What. What throws it to I Don't Know. I Don't Know throws it back to Tomorrow, Triple play. Another guy gets up and hits a long fly ball to Because. Why? I don't know! He's on third and I don't give a darn!
Abbott: What?
Costello: I said I don't give a darn!
Abbott: Oh, that's our shortstop.
Who's on First by Abbott and Costello
I think I am agreeing with a couple of the answers here in that whom only needs to used when following a preposition. Other than this requirement, who is acceptable.
Here is the usage note for whom from the Collins English dictionary:
Usage: It was formerly considered correct to use whom whenever the objective form of who was required. This is no longer thought to be necessary and the objective form who is now commonly used, even in formal writing: there were several people there who he had met before. Who cannot be used directly after a preposition - the preposition is usually displaced, as in the man (who) he sold his car to. In formal writing whom is preferred in sentences like these: the man to whom he sold his car. There are some types of sentence in which who cannot be used: the refugees, many of whom were old and ill, were allowed across the border
If you use whom in the formerly accepted manner, people will find it odd, just as they would other archaic forms of speech, such as thine, ye, or whilst.
To be honest not many native speakers actually use whom any more. When I use it I get funny looks. I think it is going the same way as the use of 'one'.
pronoun case (who and whom are discussed)
I heard a good description of how funny "whom" would sound if it were always used correctly. It had to do with the Beetles' song "Who do you love?". If they wanted to be correct they would have named the song "Whom do you love?", because they are asking about the object (the person you love). Although correct, it would just sound silly.
Who = quién
Whom = a quién
