'To whom are you talking' ----=> 'Who(m) are you talking to?'
Is in the latter sentence required 'whom' or 'who'?
The first one is obvious but I am 'fifty-fifty' concerning the second. (Is it 'who'?)
'Whom' marks the dative case. It's rather archaic and is well on its way to being phased out. But in really "standard" English, "whom are you talking to?" is the prescribed one. But I think everywhere now, schools are beginning to accept both as acceptable. Both are acceptable, hence your fifty-fifty sentiments.
First of all thanks.

Could you please tell me if the following are OK:

1) Who are you waiting for? -- I am used to seeing it but what's the actual difference between this one and the sentence given in the first post? (besides the preposition)

2) Who are you looking at? -- does this one also considers to be correct in the both forms?
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Both are ok. But if you wanted to be really proper and old-fashioned you'd say:

1a) Whom are you waiting for?
2a) Whom are you looking at?

To explain why this is the case might be abit more complicated, bear with me:

As you already know, 'whom' marks for the dative case, which is often the noun in the place of the indirect object or after a preposition. So the subject takes the nominative case, the direct object the accusative case and the indirect object the dative case:

Mary gave the book to Jane.
nom. acc. dat.

You are waiting for whom
nom. dat.

So, sentences 1a and 2a start out as:

1b) You are waiting for whom
2b) You are looking at whom

If you want change it into a question, you flip 'you are' around and move 'whom' to the front. Which is how most questions in English are formed.

Do you speak any other languages other than english? If your language is marked for case examples in that language might help.
Yes I speak two additional languages but I'd rather not translate things especially when it comes to grammar and even more especially when it comes to proverbs.Emotion: smile

Tell me please, are the 'old-fashioned' sentences (Whom are you...) more formal?
Tell me please, are the 'old-fashioned' sentences (Whom are you...) more formal?

Yes they are.
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