What is register?
Register is the level of formality in what you say or write. The same message can be formal, neutral or informal, and grammar is a big part of the difference, not only vocabulary. Good English is not always formal English: the best register is the one that fits the reader and the situation.
Formal: Should you require further information, please do not hesitate to contact us.
Informal: Need anything else? Just let me know.
How grammar changes register
| Grammar choice | Formal | Informal |
|---|---|---|
| Contractions | I am unable to attend. | I can't make it. |
| Voice | Payment must be received by Friday. | Please pay by Friday. |
| Nouns vs verbs | Our decision to expand was based on demand. | We decided to expand because people wanted it. |
| Preposition position | the client to whom I spoke | the client I spoke to |
| Who / whom | Whom did you invite? | Who did you invite? |
| Verbs | We will investigate the problem. | We'll look into the problem. |
| Conditionals | Should you need help, ... | If you need help, ... |
| General pronoun | One should always back up files. | You should always back up your files. |
| Missing words | — | Sounds good. Got it. |
When to use formal and informal grammar
1. Contractions
Contractions (I'm, don't, we'll, it's) are normal in speech, messages and most work emails. Full forms are expected in formal letters, reports and academic essays.
- Informal: We're sorry, but we can't offer a refund.
- Formal: We are sorry, but we are unable to offer a refund.
2. Passive voice for an impersonal tone
The passive hides the person who acts. This makes a message sound official and less personal.
- Neutral: We will review your application next week.
- Formal: Your application will be reviewed next week.
- Formal: It has been decided that the office will close early on Friday.
See Passive Voice for the forms.
3. Nouns instead of verbs
Formal writing often turns actions into nouns. This is called nominalisation.
- Neutral: Because the costs rose, we cancelled the event.
- Formal: The rise in costs led to the cancellation of the event.
See Nominalisation for how to do this well.
4. Prepositions and whom
In formal English, the preposition can move to the front of a relative clause or question, followed by whom or which. In everyday English, the preposition stays at the end.
| Formal | Informal / neutral |
|---|---|
| To whom should I send the form? | Who should I send the form to? |
| the colleague with whom I share an office | the colleague I share an office with |
| the project on which we are working | the project we're working on |
Ending a sentence with a preposition is not wrong. It is the normal pattern in neutral English.
5. Phrasal verbs vs single-word verbs
Many phrasal verbs have a more formal single-word partner. Phrasal verbs are not wrong in formal writing, but a single verb often sounds more precise.
| Phrasal verb (neutral / informal) | Single verb (more formal) |
|---|---|
| find out | discover, establish |
| put off | postpone |
| look into | investigate |
| carry on | continue |
| get in touch with | contact |
| set up | establish |
See Phrasal Verbs.
6. Inversion and the subjunctive (formal)
Formal letters and contracts use some structures that are rare in conversation.
- Should you have any questions, please contact me. (= If you have any questions)
- Were the contract to be cancelled, a fee would apply. (= If the contract were cancelled)
- We recommend that each employee complete the training. (subjunctive: base form, no -s)
See Inversion and The Subjunctive.
7. Ellipsis in casual speech (informal)
In conversation and texts, people often leave out the subject and the auxiliary verb when the meaning is clear. (Ellipsis = leaving words out.)
- Sounds good. (= That sounds good.)
- Want a coffee? (= Do you want a coffee?)
- See you tomorrow. (= I'll see you tomorrow.)
- Got it, thanks. (= I've got it.)
See Ellipsis and Substitution.
8. Other informal features
- Like as a conjunction: Like I said, we're closed on Monday. (Formal: As I said, ...)
- There's + plural noun: There's two problems. (Formal and careful neutral English: There are two problems.)
- Starting with And or But: common in neutral writing, less common in very formal writing.
The same message in three registers
| Formal | Neutral | Informal |
|---|---|---|
| I would be grateful if you could send the report by Friday. | Could you send the report by Friday? | Can you send the report by Friday? |
| We regret to inform you that the event has been cancelled. | Unfortunately, the event has been cancelled. | Sorry, the event's off. |
| Please find attached the requested documents. | I've attached the documents you asked for. | Here are the docs. |
| Should you have any questions, do not hesitate to contact me. | If you have any questions, please let me know. | Any questions, just ask. |
Work emails
For most work emails, a neutral register is a safe choice: polite, clear, with contractions and simple verbs. Save the formal register for official letters, complaints, legal or financial matters, and first messages to senior people you have never met.
Neutral: Hi Priya, Thanks for sending the schedule. I've made two small changes. Could you check them before Thursday? Best, Daniel
Formal: Dear Ms. Patel, Thank you for sending the schedule. I have made two minor amendments. I would be grateful if you could review them before Thursday. Kind regards, Daniel Moreau
For softening requests and opinions, see Hedging Language.
Common mistakes
1. Using whom as a subject
- Wrong:
The candidate whom we think is the strongest has withdrawn. - Correct: The candidate who we think is the strongest has withdrawn.
Who is the subject of is. Do not use whom just because it sounds formal.
2. Using who directly after a preposition
- Wrong:
To who should I address the letter? - Correct: To whom should I address the letter? / Who should I address the letter to?
Directly after a preposition, only whom is correct.
3. Mixing registers in one message
- Wrong:
Dear Sir or Madam, wanna meet up to discuss the contract? - Correct: Dear Sir or Madam, I would like to arrange a meeting to discuss the contract.
A formal greeting with a very informal body sounds strange. Choose one level and keep it.
4. Switching between one and you
- Wrong:
One should check your work carefully. - Correct: One should check one's work carefully. / You should check your work carefully.
If you start with one, continue with one's. In most modern writing, you is more natural.
5. Being too formal for the situation
- Too formal (text to a friend):
I regret to inform you that I shall be unable to attend. - Natural: Sorry, I can't make it.
Very formal grammar in a casual message can sound cold or sarcastic.
6. Writing a formal sentence with informal grammar
- Wrong (essay):
There's lots of reasons why people move to cities. - Correct: There are many reasons why people move to cities.
Quick reference
| Feature | Formal | Neutral | Informal |
|---|---|---|---|
| Contractions | no | yes | yes |
| Whom | yes | sometimes | rarely |
| Preposition at end | avoided | normal | normal |
| Passive for tone | often | sometimes | rarely |
| Phrasal verbs | fewer | yes | yes |
| Inversion (Should you ...) | yes | rarely | no |
| Leaving out subject (Sounds good) | no | no | yes |
Common questions
Is it wrong to end a sentence with a preposition?
No. "Who did you speak to?" is correct English. Moving the preposition to the front ("To whom did you speak?") is a formal choice, not a grammar rule.
Do I still need 'whom'?
In formal writing, yes, especially directly after a preposition (to whom, of whom, with whom). In speech and neutral writing, who is normal as an object: "Who did you meet?"
Can I use contractions in a work email?
Yes, in most work emails contractions are normal and sound friendly. Avoid them in formal letters, official complaints, reports and academic essays.
Practise next
- Nominalisation — the noun-heavy style of formal writing
- The Subjunctive — formal structures like 'We suggest that he be informed'
- Hedging Language — polite, careful language for emails and essays
- Ellipsis and Substitution — what you can leave out in casual English
- C2 Subjunctive and Formal Structures quiz — test formal grammar