Page 435 - Practical English Usage 3ed - Michael Swan, Oxford

personal pronouns (I): basic information 428
3 other uses of object forms: It was her
Me, him, her, us and them are used not only as objects, but also as complements after be, and in short answers, especially in an informal style.
Who said that? - (It was) her.
Who's there? - Me.
In a more formal style, we use subject form + verb where possible.
Who said that? -She did. (BUT NOT 5ite:)
It is possible to use a subject form alone after be (e.g. It is I; It was he), but this is extremely formal, and is usually considered over-correct.
Object forms are also common in double subjects in informal speech.
John and me are going skiing this weekend.
This is considered incorrect in more formal usage (see 429.1). For sentences like It's me tllat needs lIelp, see 429.3.
4 Personal pronouns cannot be left out
We cannot normally leave out personal pronouns, even if the meaning is clear without them (for some exceptions, see 429.11).
It's raining. (NOT {S I'tliniltg.)
She loved the picture because it reminded her ofhome. (NOT ••• beettrtSe
reminded her (Jf h(Jme.)
They arrested Alex and put him in prison. (NOT ••• anti put in prisBn.) Have some chocolate. -No, I don't like it. (NOT ••• {ti(m't like.)
5 One subject is enough
One subject is enough. We do not usually use a personal pronoun to repeat a subject that comes in the same clause.
My car is parked outside. (NOT My M r it is parked (Jfttsitle.)
The boss really gets on my nerves. (NOT The b6S1J he really gets (In Ifty nel'fles.) The situation is terrible. (NOT It is terf'ibie the siftitlti(Jn.)
There are exceptions in very informal speech (see 514).
He's not a bad bloke, Jeff. It's a horrible place, London.
For it as a preparatory subject or object, see 446-447.
6 personal and relative pronouns: she or who, not both
We do not use personal pronouns to repeat the meaning of relative pronouns (see 494.7).
That's the girl who lives in the flat upstairs. (NOT ••• ttffl(J she litJeS .•.) Here's the money (that) you lent me. (NOT ••• (that)16ft lent me it.)
7 it referring to nothing, the situation, etc.
It not only refers to the names of particular things. We can also use it to refer to indefinite pronouns like nothing, anything, everything.
Nothing happened. did it? Everything's all right, isn't it?
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