Register: formal and informal grammar

To whom did you speak, or who did you speak to: choosing grammar to suit a formal or an informal situation.

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Register is how formal or informal language is. Words show it, but so does grammar: the same idea can be built in a formal way for a report, a contract or a speech, and in an informal way for a chat or a message to a friend. Both are correct English. At C2 the skill is to choose one register and keep to it, and to recognise the formal forms when you read them.

Informal	Formal
Who did you speak to?	To whom did you speak?
If you need any help, just call.	Should you require any assistance, please call.
We think the plan will fail.	It is felt that the plan will fail.
They changed the rules, so prices went up.	The change in the rules led to higher prices.
I've never seen such a mess.	Never have I seen such a mess.
Like I said, it's too late.	As I said, it is too late.

Who and whom

Whom is the object form of who. In formal English it is used for the object, and always directly after a preposition. In everyday English, who is normal for the object, with the preposition at the end.

Whom did the committee appoint?
Formal. In speech: Who did they appoint?
The candidate to whom the job was offered has accepted.
Incorrect: To who should I send the application?
Correct: To whom should I send the application? / Who should I send the application to?
Directly after a preposition, only whom is possible.
Incorrect: Whom shall I say is calling?
Correct: Who shall I say is calling?
Who is the subject of is calling, so whom is wrong here even in formal English.

The preposition: at the end or at the front

A preposition can go at the end of a question or a relative clause, which is normal in speech, or at the front with whom or which, which is formal. Both are correct. After a preposition, use which or whom, never that.

The hotel we stayed at was lovely.
The hotel at which we stayed was lovely.
Formal.
Incorrect: This is the report in that the figures were published.
Correct: This is the report in which the figures were published. / ... the report that the figures were published in.
That cannot follow a preposition.

In a phrasal verb, the particle belongs to the verb, so it cannot move to the front.

Incorrect: These are the children after whom she looks.
Correct: These are the children (who) she looks after.
Look after is a phrasal verb; after stays with look.

Formal structures

Formal writing prefers structures that sound less personal and more distant. You have met them at C1: the passive and it is said that, nominalisation, inverted conditionals and inversion after negative words.

It has been decided that the office will close.
Informal: We've decided to close the office.
The introduction of the new system caused delays.
Informal: When they introduced the new system, there were delays.
Had we known about the problem, we would have acted.
Informal: If we'd known ...
Under no circumstances should the door be left open.
Informal: Never leave the door open.

Informal structures

Informal speech and messages leave words out, use contractions and get, and put a question tag or a comment at the end. In formal writing, use the full forms.

Sounds good. See you at eight.
The subject is left out.
I got told off for being late.
Formal: I was reprimanded for being late.
It's a great idea, isn't it?
There's a few things I need to tell you.
Common in speech; in writing use There are a few things ...

Pronouns: between you and me, than I or than me

After a preposition, the object form is correct in every register. After than and as, both forms are used: the object form is normal in speech; the subject form needs a verb after it, or it sounds very formal (older than I).

Incorrect: Between you and I, the plan won't work.
Correct: Between you and me, the plan won't work.
Between is a preposition, so it takes the object form me.
She is older than me.
She is older than I am.
Neutral, and the safer choice in writing.

They for one person whose gender is not known or not relevant is correct in formal and informal English: Each applicant must sign their form.

Keeping one register

A common register mistake at advanced level is a mix: a formal sentence with one informal phrase in it, or the other way round. Read a text again and make its grammar and its words match.

Should you require further information, please do not hesitate to contact us.
Formal throughout.
If you need more info, just give us a shout.
Informal throughout.

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