Hi,
I keep having trouble with "cleft sentences" and those kinds of things. It's you who is /are...Emotion: tongue tied Here are my guesses:
  • It's me who is, needs, wants, goes, does...
  • It's you who is, needs, wants, goes, does... (this is the singular you)
  • It's him who is, needs, wants, goes, does...
  • It's us who are, need, want, go, do...
  • It's you who are, need, want, go, do... (this is the plural you)
  • It's them who are, need, want, go, do...
You are free to give your opinions (well, as long as your opinions are right, hehehe Emotion: wink )
Thank you in advance.
You've made some very respectable guesses! (I'm convinced that there are no right answers to this question, by the way! Emotion: smile )

The It's or It is or It was and the who are invariable in all versions of this formula.

The controversy revolves around two other factors.
Should the pronoun before who be in the nominative (I, you, he, she, we, they) or in the objective (me, you, him, her, us, them) case?
Should the verb after who agree only in number or in number and person with the antecedent pronoun? (This factor is important only in the cases of I am and You are.)
______________

Taking I am tired as the base sentence, the four cleft versions which are possible are:

It is I who am tired. (Nominative, number, person)
It is I who is tired.
(Nominative, number)
It is me who am tired.
(Objective, number, person)
It is me who is tired. (Objective, number)
___________

With You are tired, you singular. (Cases conflated.)

It is you who are tired. (Nom/Obj, number, person)
It is you who is tired. (Nom/Obj, number)
___________

With You are tired, you plural, only one version is possible. (Cases conflated and number and person conflated)

It is you who are tired. (Nom/Obj, number/person)
___________

Two versions are possible with each of the remaining pronouns. (Number and person conflated)

It is [he / she] who is tired. (Nominative, number)
It is [him / her] who is tired. (Objective, number)
It is [we / they] who are tired. (Nominative, number)
It is [us / them] who are tired. (Objective, number)
___________

My understanding, right or wrong, is that the most formal and academic usage requires the It is I who am pattern, i.e., nominative case and both number and person agreement. Some people argue that I who is is fine. I don't think anyone argues in favor of me who am. My impression is that, informally in conversation, me who is might be used.
Following the idea that the maximum of agreement is needed for formal, academic use, ... you who are ... is the version to use, whether you is singular or plural. Likewise, ... [he / she / we / they] who [is / is / are / are]... are the more formal forms.
__________

Where I live, hardly anybody uses the forms shown above very much. We prefer to express the same meaning with the following paradigm:

I'm the one who's tired.
You're the one who's tired.
He's/She's the one who's tired.
We're the ones who are tired.
You're the ones who are tired.
They're the ones who are tired.


This topic is very controversial, and others are sure to have their own opinions on it. Emotion: smile

CJ
Thank you so much CalifJim! Emotion: smile
CalifJim(I'm convinced that there are no right answers to this question, by the way! Emotion: smile )
Well, you are right!

I have been looking for examples on the Net, the guesses you've read are what seems to be more usual (dammit, what seem/seemsagain! Emotion: crying ). By the way, in formal writing I guess the best thing to do is to avoid those kinds of constructions completely. You know, I just asked two American friends this thing. Well, they don't know! And they don't know the question of"what seem/seems" either! I've read posts in forums, I found teachers'opinions, native speakers'opinions, online grammar tips, and it turned out to be a great mess since they often disagree with each other. But what it is important is that often people don't seem to notice these "little mistakes". That is, nobody knows what is correct between "My friend are what makes me happy" and "...are what make me happy", but people accept or use both of them.

My goal is to know idiomatic english, not to know a lot of rules that probably I'll never remember and nobody uses. So I think I'll use the sentences I wrote as guesses (in informal contexts of course), and make or makes in sentences like "My friends are what makes me feel better". I feel this choices are idiomatic, though they might be not grammatically correct. Obviously, structures like "we are the ones..." often are what sounds fine. (aargh, again that damn what Emotion: angry )

I just don't know why the thread I start are always about controversial subjects. Maybe I'm silmply a troublemaker. Emotion: wink

Thank you very much for your reply Califjim.
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The above post is mine, I forgot to login, as always. Emotion: smile

I found out something on the Net about this issue, and they disagree with each other:

It is you who are leaving ---- http://www.zianet.com/jkline/u3pnagr.htm

"it is you who is responsible for this" - not "are." ---- http://www.stage-door.org/stampact/traps.html

the "who" refers to the "you," so we want "have." ---- http://grammar.ccc.commnet.edu/grammar/grammarlogs3/grammarlogs467.htm

As you can see, they all say different things. But what I did then was this: again, I tryed to find what is more usual. I've checked a lot of websites, even song databases and American blogs. So:

  • It's you who/that is trying to understand.

  • It's you who/that needs an answer.

  • It's you who/that doesn't understand this at all.
But notice the plural verb here:

  • It's you guys who/that are trying to understand.

  • It's you learners who/that need an answer.

  • It's you who/that don't understand this at all. (plural you, you readers, you guys)
I believe the tenses used in those sentences are the most idiomatic and most accepted, even if they might be grammatically wrong.

If anyone has some different opinions or want to tell us what they use in everyday's speech, they are free to post in this thread. Emotion: smile
In Google, there are about 134,000 results for "it is you who are" and 69,500 results for "it is you who is".
Thank you, CJ. Great post!
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I always trust Google searches in such issues, however this one is completely invalid, because the "you" in "it is you who are" may also refer to a plural subject.

Thank you CalifJim and Kooyeen. Great post!
In my opinion the correct forms are:

- my friends are what makes me happy

- it is I who is

because "what" stands for "the thing that" (singular), and "who" stands for "the person who" (singular again).
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